Cisco ASR 9000 Series Aggregation Services Router IP Addresses and Services Command Reference, Release 4.1
Access List Commands
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Access List Commands

Access List Commands

This module describes the Cisco IOS XR software commands used to configure IP Version 4 (IPv4) and IP Version 6 (IPv6) access lists on Cisco ASR 9000 Series Aggregation Services Routers .

An access control list (ACL) consists of one or more access control entries (ACEs) that collectively define the network traffic profile. This profile can then be referenced by Cisco IOS XR Software software features such as traffic filtering, priority or custom queueing, and dynamic access control. Each ACL includes an action element (permit or deny) and a filter element based on criteria such as source address, destination address, protocol, and protocol-specific parameters.

For detailed information about ACL concepts, configuration tasks, and examples, see the Cisco  ASR  9000 Series Aggregation Services Router IP Addresses and Services Configuration Guide.

clear access-list ipv4

To clear IPv4 access list counters, use the clear access-list ipv4 command in EXEC mode.

clear access-list ipv4 access-list name [ sequence-number | hardware { ingress | egress}] [interface type interface-path-id] [ location node-id | sequence number ]

Syntax Description

access-list-name

Name of a particular IPv4 access list. The name cannot contain a spaces or quotation marks, but can include numbers.

sequence-number

(Optional) Specific sequence number with which counters are cleared for an access list. Range is 1 to 2147483644 .

hardware

Identifies the access list as an access group for an interface.

ingress

Specifies an inbound direction.

egress

Specifies an outbound direction.

interface

(Optional) Clears the interface statistics.

type

Interface type. For more information, use the question mark (?) online help function.

interface-path-id

Physical interface or virtual interface.

Note   

Use the show interfaces command to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

location node-id

(Optional) Clears hardware resource counters from the designated node. The node-id argument is entered in the rack/slot/module notation.

sequence number

(Optional) Clears counters for an access list with a specific sequence number. Range is 1 to 2147483644 .

Command Default

The default clears the specified IPv4 access list.

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the clear access-list ipv4 command to clear counters for a specified configured access list. Use a sequence number to clear counters for an access list with a specific sequence number.

Use the hardware keyword to clear counters for an access list that was enabled using the ipv4 access-group command.

Use an asterisk ( *) in place of the access-list-name argument to clear all access lists.


Note


An access list can be shared among multiple interfaces. Clearing hardware counters clears all counters for all interfaces that use the specified access list in a given direction (ingress or egress).


Task ID

Task ID

Operations

basic-services

read, write

acl

read, write

bgp

read, write, execute

Examples

In the following example, counters for an access list named marketing are cleared:


RP/0/RSP0/CPU0:router# show access-lists ipv4 marketing

ipv4 access-list marketing
  10 permit ip 192.168.34.0 0.0.0.255 any (51 matches)
  20 permit ip 172.16.0.0 0.0.255.255 any (26 matches)
  30 deny tcp host 172.16.0.0 eq bgp host 192.168.202.203 30 (5 matches)

RP/0/RSP0/CPU0:router# clear access-list ipv4 marketing

RP/0/RSP0/CPU0:router# show access-lists ipv4 marketing

ipv4 access-list marketing
  10 permit ip 192.168.34.0 0.0.0.255 any
  20 permit ip 172.16.0.0 0.0.255.255 any 
  30 deny tcp host 172.16.0.0 eq bgp host 192.168.202.203 30

In the following example, counters for an access list named acl_hw_1 in the outbound direction are cleared:

RP/0/RSP0/CPU0:router# show access-lists ipv4 acl_hw_1 hardware egress location 0/2/cp0

ipv4 access-list acl_hw_1
  10 permit icmp 192.168.36.0 0.0.0.255 any (251 hw matches)
  20 permit ip 172.16.3.0 0.0.255.255 any (29 hw matches)
  30 deny tcp any any (58 hw matches)

RP/0/RSP0/CPU0:router# clear access-list ipv4 acl_hw_1 hardware egress location 0/2/cp0

RP/0/RSP0/CPU0:router# show access-lists ipv4 acl_hw_1 hardware egress location 0/2/cp0

ipv4 access-list acl_hw_1
  10 permit icmp 192.168.36.0 0.0.0.255 any
  20 permit ip 172.16.3.0 0.0.255.255 any 
  30 deny tcp any any

Related Commands

Command

Description

ipv4 access-group

Filters incoming or outgoing IPv4 traffic on an interface.

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

resequence access-list ipv4

Renumbers an existing statement and increments subsequent statements to allow a new IPv4 access list statements.

clear access-list ipv6

To clear IPv6 access list counters, use the clear access-list ipv6 command in EXEC mode.

clear access-list ipv6 access-list-name [ sequence-number | hardware { ingress | egress } ] [ interface type interface-path-id ] [ location node-id | sequence number ]

Syntax Description

access-list-name

Name of a particular IPv6 access list. The name cannot contain a spaces or quotation marks, but can include numbers.

sequence-number

(Optional) Specific sequence number for a particular access control entry (ACE) with which counters are cleared for an access list. Range is 1 to 2147483644.

hardware

(Optional) Identifies the access list as an access group for an interface.

ingress

(Optional) Specifies an inbound direction.

egress

(Optional) Specifies an outbound direction.

interface

(Optional) Clears the interface statistics.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

instance

interface-path-id

Physical interface or virtual interface.

Note   

Use the show interfaces command to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

location node-id

(Optional) Clears counters for an access list enabled on a card interface. The node-id argument is entered in the rack/slot/module notation.

sequence number

(Optional) Specifies a specific sequence number that clears access list counters. Range is 1 to 2147483644.

Command Default

The default clears the specified IPv6 access list.

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The clear access-list ipv6 command is similar to the clear access-list ipv4 command, except that it is IPv6-specific.

Use the clear access-list ipv6 command to clear counters for a specified configured access list. Use a sequence number to clear counters for an access list with a specific sequence number

Use thehardware keyword to clear counters for an access list that was enabled using the ipv6 access-group command.

Use an asterisk (*) in place of the access-list-name argument to clear all access lists.


Note


An access list can be shared among multiple interfaces. Clearing hardware counters clears all counters for all interfaces that use the specified access list in a given direction (ingress or egress).


Task ID

Task ID

Operations

basic-services

read, write

acl

read, write

network

read, write

Examples

In the following example, counters for an access list named marketing are cleared:


RP/0/RSP0/CPU0:router# show access-lists ipv6 marketing
ipv6 access-list marketing
  10 permit ipv6 3333:1:2:3::/64 any (51 matches)
  20 permit ipv6 4444:1:2:3::/64 any (26 matches)
  30 permit ipv6 5555:1:2:3::/64 any (5 matches)
RP/0/RSP0/CPU0:router# clear access-list ipv6 marketing
RP/0/RSP0/CPU0:router# show access-lists ipv6 marketing
ipv6 access-list marketing
  10 permit ipv6 3333:1:2:3::/64 any
  20 permit ipv6 4444:1:2:3::/64 any
  30 permit ipv6 5555:1:2:3::/64 any

In the following example, counters for an access list named acl_hw_1 in the outbound direction are cleared:


RP/0/RSP0/CPU0:router# show access-lists ipv6 acl_hw_1 hardware egress location 0/2/cp0
ipv6 access-list acl_hw_1
  10 permit ipv6 3333:1:2:3::/64 any (251 hw matches)
  20 permit ipv6 4444:1:2:3::/64 any (29 hw matches)
  30 deny tcp any any (58 hw matches)
RP/0/RSP0/CPU0:router# clear access-list ipv6 acl_hw_1 hardware egress location 0/2/cp0
RP/0/RSP0/CPU0:router# show access-lists ipv6 acl_hw_1 hardware egress location 0/2/cp0
ipv6 access-list acl_hw_1
  10 permit ipv6 3333:1:2:3::/64 any
  20 permit ipv6 4444:1:2:3::/64 any
  30 deny tcp any any

Related Commands

Command

Description

ipv6 access-list

Defines an IPv6 access list and enters IPv6 access list configuration mode.

copy access-list ipv4

To create a copy of an existing IPv4 access list, use the copy access-list ipv4 command in EXEC mode.

copy access-list ipv4 source-acl destination-acl

Syntax Description

source-acl

Name of the access list to be copied.

destination-acl

Name of the destination access list where the contents of the source-acl argument is copied.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the copy access-list ipv4 command to copy a configured access list. Use the source-acl argument to specify the access list to be copied and the destination-acl argument to specify where to copy the contents of the source access list. The destination-acl argument must be a unique name; if the destination-acl argument name exists for an access list or prefix list, the access list is not copied. The copy access-list ipv4 command checks that the source access list exists then checks the existing list names to prevent overwriting existing access lists or prefix lists.

Task ID

Task ID

Operations

acl

read, write

filesystem

execute

Examples

In the following example, a copy of access list list-1 is created:


RP/0/RSP0/CPU0:router# show access-lists ipv4 list-1

ipv4 access-list list-1
  10 permit tcp any any log
  20 permit ip any any
RP/0/RSP0/CPU0:router# copy access-list ipv4 list-1 list-2
RP/0/RSP0/CPU0:router# show access-lists ipv4 list-2
ipv4 access-list list-2
  10 permit tcp any any log
  20 permit ip any any

In the following example, copying the access list list-1 to list-3 is denied because a list-3 access list already exists:


RP/0/RSP0/CPU0:router# copy access-list ipv4 list-1 list-3

list-3 exists in access-list

RP/0/RSP0/CPU0:router# show access-lists ipv4 list-3

ipv4 access-list list-3
  10 permit ip any any 
  20 deny tcp any any log

Related Commands

Command

Description

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

show access-lists ipv4

Displays the contents of all current IPv4 access lists.

copy access-list ipv6

To create a copy of an existing IPv6 access list, use the copy access-list ipv6 command in EXEC mode.

copy access-list ipv6 source-acl destination-acl

Syntax Description

source-acl

Name of the access list to be copied.

destination-acl

Destination access list where the contents of the source-acl argument is copied.

Command Default

No default behavior or value

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the copy access-list ipv6 command to copy a configured access list. Use the source-acl argument to specify the access list to be copied and the destination-acl argument to specify where to copy the contents of the source access list. The destination-acl argument must be a unique name; if the destination-acl argument name exists for an access list or prefix list, the access list is not copied. The copy access-list ipv6 command checks that the source access list exists then checks the existing list names to prevent overwriting existing access lists or prefix lists.

Task ID

Task ID

Operations

acl

read, write

filesystem

execute

Examples

In the following example, a copy of access list list-1 is created:


RP/0/RSP0/CPU0:router# show access-lists ipv6 list-1

ipv6 access-list list-1
  10 permit tcp any any log
  20 permit ipv6 any any

RP/0/RSP0/CPU0:router# copy access-list ipv6 list-1 list-2

RP/0/RSP0/CPU0:router# show access-lists ipv6 list-2

ipv6 access-list list-2
  10 permit tcp any any log
  20 permit ipv6 any any

In the following example, copying access list list-1 to list-3 is denied because a list-3 access list already exists:


RP/0/RSP0/CPU0:router# copy access-list ipv6 list-1 list-3

list-3 exists in access-list

RP/0/RSP0/CPU0:router# show access-lists ipv6 list-3
ipv6 access-list list-3
  10 permit ipv6 any any 
  20 deny tcp any any log

Related Commands

Command

Description

ipv6 access-list

Defines an IPv6 access list and enters IPv6 access list configuration mode.

show access-lists ipv6

Displays the contents of all current IPv6 access lists.

deny (IPv4)

To set conditions for an IPv4 access list, use the deny command in access list configuration mode. There are two versions of the deny command: deny (source), and deny (protocol). To remove a condition from an access list, use the no form of this command.

[sequence-number] deny source [source-wildcard] [ log | log-input ]

[sequence-number]denyprotocol source source-wildcard destination destination-wildcard[ precedenceprecedence] [ dscpdscp] [ fragments] [ packet-length operator packet-length value] [ log | log-input] [ ttl ttl value [value1....value2]]

no sequence-number

Internet Control Message Protocol (ICMP)

[sequence-number] deny icmp source source-wildcard destination destination-wildcard [icmp-type] [icmp-code] [ precedence precedence ] [ dscp dscp ] [fragments] [ log | log-input ] [icmp-off]

Internet Group Management Protocol (IGMP)

[sequence-number] deny igmp source source-wildcard destination destination-wildcard [igmp-type] [ precedence precedence ] [ dscp value ] [fragments] [ log | log-input ]

User Datagram Protocol (UDP)

[sequence-number] deny udp source source-wildcard [ operator { port | protocol-port } ] destination destination-wildcard [ operator { port | protocol-port } ] [ precedence precedence ] [ dscp dscp ] [fragments] [ log | log-input ]

Syntax Description

sequence-number

(Optional) Number of the deny statement in the access list. This number determines the order of the statements in the access list. The number can be from 1 to 2147483644. (By default, the first statement is number 10, and the subsequent statements are incremented by 10.) Use the resequence access-list command to change the number of the first statement and increment subsequent statements of a configured access list.

source

Number of the network or host from which the packet is being sent. There are three alternative ways to specify the source:

  • Use a 32-bit quantity in four-part dotted-decimal format.
  • Use the any keyword as an abbreviation for a source and source-wildcard of 0.0.0.0 255.255.255.255.
  • Use the host source combination as an abbreviation for a source and source-wildcard of source 0.0.0.0.

source-wildcard

Wildcard bits to be applied to the source. There are three alternative ways to specify the source wildcard:

  • Use a 32-bit quantity in four-part dotted-decimal format. Place ones in the bit positions you want to ignore.
  • Use the any keyword as an abbreviation for a source and source-wildcard of 0.0.0.0 255.255.255.255.
  • Use the host source combination as an abbreviation for a source and source-wildcard of source 0.0.0.0.

protocol

Name or number of an IP protocol. It can be one of the keywords ahp , esp , eigrp , gre , icmp , igmp , igrp , ip , ipinip , nos , ospf , pim , pcp , tcp , or udp , or an integer from 0 to 255 representing an IP protocol number. To match any Internet protocol (including ICMP, TCP, and UDP), use the ip keyword. ICMP, and TCP allow further qualifiers, which are described later in this table.

destination

Number of the network or host to which the packet is being sent. There are three alternative ways to specify the destination:

  • Use a 32-bit quantity in four-part dotted-decimal format.
  • Use the any keyword as an abbreviation for the destination and destination-wildcard of 0.0.0.0 255.255.255.255.
  • Use the host destination combination as an abbreviation for a destination and destination-wildcard of destination 0.0.0.0.

destination-wildcard

Wildcard bits to be applied to the destination. There are three alternative ways to specify the destination wildcard:

  • Use a 32-bit quantity in four-part dotted-decimal format. Place ones in the bit positions you want to ignore.
  • Use the any keyword as an abbreviation for a destination and destination-wildcard of 0.0.0.0 255.255.255.255.
  • Use the host destination combination as an abbreviation for a destination and destination-wildcard of destination 0.0.0.0.

precedence precedence

(Optional) Packets can be filtered by precedence level (as specified by a number from 0 to 7) or by the following names:

  • routine —Match packets with routine precedence (0)
  • priority —Match packets with priority precedence (1)
  • immediate —Match packets with immediate precedence (2)
  • flash —Match packets with flash precedence (3)
  • flash-override —Match packets with flash override precedence (4)
  • critical —Match packets with critical precedence (5)
  • internet —Match packets with internetwork control precedence (6)
  • network —Match packets with network control precedence (7)

dscp dscp

(Optional) Differentiated services code point (DSCP) provides quality of service control. The values for dscp are as follows:

  • 063–Differentiated services codepoint value
  • af11—Match packets with AF11 dscp (001010)
  • af12—Match packets with AF12 dscp (001100)
  • af13—Match packets with AF13 dscp (001110)
  • af21—Match packets with AF21 dscp (010010)
  • af22—Match packets with AF22 dscp (010100)
  • af23—Match packets with AF23 dscp (010110)
  • af31—Match packets with AF31 dscp (011010)
  • af32—Match packets with AF32 dscp (011100)
  • af33—Match packets with AF33 dscp (011110)
  • af41—Match packets with AF41 dscp (100010)
  • af42—Match packets with AF42 dscp (100100)
  • af43—Match packets with AF43 dscp (100110)
  • cs1—Match packets with CS1 (precedence 1) dscp (001000)
  • cs2—Match packets with CS2 (precedence 2) dscp (010000)
  • cs3—Match packets with CS3 (precedence 3) dscp (011000)
  • cs4—Match packets with CS4 (precedence 4) dscp (100000)
  • cs5—Match packets with CS5 (precedence 5) dscp (101000)
  • cs6—Match packets with CS6 (precedence 6) dscp (110000)
  • cs7—Match packets with CS7 (precedence 7) dscp (111000)
  • default—Default DSCP (000000)
  • ef—Match packets with EF dscp (101110)

fragments

(Optional) Causes the software to examine fragments of IPv4 packets when applying this access list entry. When this keyword is specified, fragments are subject to the access list entry.

log

(Optional) Causes an informational logging message about the packet that matches the entry to be sent to the console. (The level of messages logged to the console is controlled by the logging console command.)

The message includes the access list number, whether the packet was permitted or denied; the protocol, whether it was TCP, UDP, ICMP, or a number; and, if appropriate, the source and destination addresses and source and destination port numbers. The message is generated for the first packet that matches a flow, and then at 5-minute intervals, including the number of packets permitted or denied in the prior 5-minute interval.

log-input

(Optional) Provides the same function as the log keyword, except that the logging message also includes the input interface.

ttl

(Optional) Turns on matching against time-to-life (TTL) value.

ttl value [value1. . value2[

(Optional) TTL value used for filtering. Range is 1 to 255.

If only value is specified, the match is against this value.

If both value1 and value2 are specified, the packet TTL is matched against the range of TTLs between value1 and value2 .

icmp-off

(Optional) Turns off ICMP generation for denied packets.

icmp-type

(Optional) ICMP message type for filtering ICMP packets. Range is from 0 to 255.

icmp-code

(Optional) ICMP message code for filtering ICMP packets. Range is from 0 to 255.

igmp-type

(Optional) IGMP message type (0 to 15) or message name for filtering IGMP packets, as follows:

  • dvmrp
  • host-query
  • host-report
  • mtrace
  • mtrace-response
  • pim
  • precedence
  • trace
  • v2-leave
  • v2-report
  • v3-report

operator

(Optional) Operator is used to compare source or destination ports. Possible operands are lt (less than), gt (greater than), eq (equal), neq (not equal), and range (inclusive range).

If the operator is positioned after the source and source-wildcard values, it must match the source port.

If the operator is positioned after the destination and destination-wildcard values, it must match the destination port.

If the operator is positioned after the ttl keyword, it matches the TTL value.

The range operator requires two port numbers. All other operators require one port number.

port

Decimal number of a TCP or UDP port. A port number is a number from 0 to 65535.

TCP ports can be used only when filtering TCP. UDP ports can be used only when filtering UDP.

protocol-port

Name of a TCP or UDP port. TCP and UDP port names are listed in the “Usage Guidelines” section.

TCP port names can be used only when filtering TCP. UDP port names can be used only when filtering UDP.

established

(Optional) For the TCP protocol only: Indicates an established connection.

match-any

(Optional) For the TCP protocol only: Filters on any combination of TCP flags.

match-all

(Optional) For the TCP protocol only: Filters on all TCP flags.

+ | -

(Required) For the TCP protocol match-any , match-all : Prefix flag-name with + or - . Use the + flag-name argument to match packets with the TCP flag set. Use the - flag-name argument to match packets when the TCP flag is not set.

flag-name

(Optional) For the TCP protocol match-any , match-all . Flag names are: ack , fin , psh , rst , syn .

Command Default

There is no specific condition under which a packet is denied passing the IPv4 access list.

ICMP message generation is enabled by default.

Command Modes

IPv4 access list configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the deny command following the ipv4 access-list command to specify conditions under which a packet cannot pass the access list.

By default, the first statement in an access list is number 10, and the subsequent statements are incremented by 10.

You can add permit, deny, or remark statements to an existing access list without retyping the entire list. To add a new statement anywhere other than at the end of the list, create a new statement with an appropriate entry number that falls between two existing entry numbers to indicate where it belongs.

If you want to add a statement between two consecutively numbered statements (for example, between lines 10 and 11), first use the resequence access-list command to renumber the first statement and increment the entry number of each subsequent statement. The increment argument causes new, unused line numbers between statements. Then add a new statement with the entry-number argument, specifying where it belongs in the access list.

The following is a list of precedence names:

  • critical
  • flash
  • flash-override
  • immediate
  • internet
  • network
  • priority
  • routine

The following is a list of ICMP message type names:

  • administratively-prohibited
  • alternate-address
  • conversion-error
  • dod-host-prohibited
  • dod-net-prohibited
  • echo
  • echo-reply
  • general-parameter-problem
  • host-isolated
  • host-precedence-unreachable
  • host-redirect
  • host-tos-redirect
  • host-tos-unreachable
  • host-unknown
  • host-unreachable
  • information-reply
  • information-request
  • mask-reply
  • mask-request
  • mobile-redirect
  • net-redirect
  • net-tos-redirect
  • net-tos-unreachable
  • net-unreachable
  • network-unknown
  • no-room-for-option
  • option-missing
  • packet-too-big
  • parameter-problem
  • port-unreachable
  • precedence-unreachable
  • protocol-unreachable
  • reassembly-timeout
  • redirect
  • router-advertisement
  • router-solicitation
  • source-quench
  • source-route-failed
  • time-exceeded
  • timestamp-reply
  • timestamp-request
  • traceroute
  • ttl-exceeded
  • unreachable

The following is a list of TCP port names that can be used instead of port numbers. Refer to the current Assigned Numbers RFC to find a reference to these protocols. You can find port numbers corresponding to these protocols by typing a ? in the place of a port number.

  • bgp
  • chargen
  • cmd
  • daytime
  • discard
  • domain
  • echo
  • exec
  • finger
  • ftp
  • ftp-data
  • gopher
  • hostname
  • ident
  • irc
  • klogin
  • kshell
  • login
  • lpd
  • nntp
  • pim-auto-rp
  • pop2
  • pop3
  • smtp
  • sunrpc
  • tacacs
  • talk
  • telnet
  • time
  • uucp
  • whois
  • www

The following UDP port names can be used instead of port numbers. Refer to the current Assigned Numbers RFC to find a reference to these protocols. You can find port numbers corresponding to these protocols by typing a ? in the place of a port number.

  • biff
  • bootpc
  • bootps
  • discard
  • dnsix
  • domain
  • echo
  • isakmp
  • mobile-ip
  • nameserver
  • netbios-dgm
  • netbios-ns
  • netbios-ss
  • ntp
  • pim-auto-rp
  • rip
  • snmp
  • snmptrap
  • sunrpc
  • syslog
  • tacacs
  • talk
  • tftp
  • time
  • who
  • xdmcp

Use the following flags in conjunction with the match-any and match-all keywords and the + and - signs to select the flags to display:

For example, match-all + ack + syn displays TCP packets with both the ack and syn flags set, or match-any + ack - syn displays the TCP packets with the ack set or the syn not set.

Task ID

Task ID

Operations

ipv4

read, write

acl

read, write

Examples

The following example shows how to set a deny condition for an access list named Internetfilter:


RP/0/RSP0/CPU0:router(config)# ipv4 access-list Internetfilter
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 10 deny 192.168.34.0 0.0.0.255
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 20 deny 172.16.0.0 0.0.255.255
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 25 deny tcp host 172.16.0.0 eq bgp host 192.168.202.203 range 1300 1400
RP/0/RSP0/CPU0:router(config-ipv4-acl)# permit 10.0.0.0 0.255.255.255

Related Commands

Command

Description

ipv4 access-group

Filters incoming or outgoing IPv4 traffic on an interface.

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

permit (IPv4)

Sets the permit conditions for an IPv4 access list.

remark (IPv4)

Inserts a helpful remark about an IPv4 access list entry.

resequence access-list ipv4

Changes the starting entry number of the first statement in an existing IPv4 access list, and the number by which subsequent statements are incremented.

show access-lists ipv4

Displays the contents of all current IPv4 access lists.

deny (IPv6)

To set deny conditions for an IPv6 access list, use the deny command in IPv6 access list configuration mode. To remove the deny conditions, use the no form of this command.

[sequence-number] denyprotocol { source-ipv6-prefix/ prefix-length | any | host source-ipv6-address } [ operator { port | protocol-port } ] [ dscpvalue] [ routing] [ authen] [ destopts] [ fragments] [ packet-length operator packet-length value ] [ log | log-input] [ ttl operator ttl value ]

no sequence-number

Internet Control Message Protocol (ICMP)

[ sequence-number]deny icmp { source-ipv6-prefix/ prefix-length | any | host source-ipv6-address } { destination-ipv6-prefix/ prefix-length | any | host destination-ipv6-address } [ icmp-type] [ icmp-code][ dscp value] [ routing] [ authen] [ destopts] [ fragments] [ log] [ log-input] [ icmp-off]

Transmission Control Protocol (TCP)

[sequence-number]deny tcp { source-ipv6-prefix/ prefix-length | any | host source-ipv6-address } [ operator { port | protocol-port } ] { destination-ipv6-prefix/ prefix-length | any | host destination-ipv6-address } [ operator { port | protocol | port } ] [ dscpvalue] [ routing] [ authen] [ destopts] [ fragments] [ established] { match-any | match-all | + | - } [ flag-name] [ log] [ log-input]

User Datagram Protocol (UDP)

[sequence-number]deny tcp { source-ipv6-prefix/ prefix-length | any | host source-ipv6-address } [ operator { port | protocol-port } ] { destination-ipv6-prefix/ prefix-length | any | host destination-ipv6-address } [ operator { port | protocol | port } ] [ dscpvalue] [ routing] [ authen] [ destopts] [ fragments] [ established] [ flag-name] [ log] [ log-input]

Syntax Description

sequence-number

(Optional) Number of the deny statement in the access list. This number determines the order of the statements in the access list. Range is 1 to 2147483644. (By default, the first statement is number 10, and the subsequent statements are incremented by 10.) Use the resequence access-list command to change the number of the first statement and increment subsequent statements of a configured access list.

protocol

Name or number of an Internet protocol. It can be one of the keywords ahp , eigrp, esp , gre, icmp , igmp, igrp, ipinip, ipv6 , nos, ospf, pcp , tcp , or udp , or an integer in the range from 0 to 255 representing an IPv6 protocol number.

source-ipv6-prefix / prefix-length

The source IPv6 network or class of networks about which to set deny conditions.

This argument must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.

any

An abbreviation for the IPv6 prefix ::/0.

host source-ipv6-address

Source IPv6 host address about which to set deny conditions.

This source-ipv6-address argument must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.

operator {port | protocol-port}

(Optional) Operand that compares the source or destination ports of the specified protocol. Operands are lt (less than), gt (greater than), eq (equal), neq (not equal), and range (inclusive range).

If the operator is positioned after the source-ipv6-prefix / prefix-length argument, it must match the source port.

If the operator is positioned after the destination-ipv6-prefix / prefix-length argument, it must match the destination port.

The range operator requires two port numbers. All other operators require one port number.

The port argument is the decimal number of a TCP or UDP port. Range is 0 to 65535. The protocol-port argument is the name of a TCP or UDP port. TCP port names can be used only when filtering TCP. UDP port names can be used only when filtering UDP.

destination-ipv6-prefix / prefix-length

Destination IPv6 network or class of networks about which to set deny conditions.

This argument must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.

host destination-ipv6-address

Destination IPv6 host address about which to set deny conditions.

This destination-ipv6-address argument must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.

dscp value

(Optional) Matches a differentiated services code point DSCP value against the traffic class value in the Traffic Class field of each IPv6 packet header. Range is 0 to 63.

routing

(Optional) Matches source-routed packets against the routing extension header within each IPv6 packet header.

authen

(Optional) Matches if the IPv6 authentication header is present.

destopts

(Optional) Matches if the IPv6 destination options header is present.

fragments

(Optional) Matches noninitial fragmented packets where the fragment extension header contains a nonzero fragment offset. The fragments keyword is an option only if the operator [ port-number ] arguments are not specified.

log

(Optional) Causes an informational logging message about the packet that matches the entry to be sent to the console. (The level of messages logged to the console is controlled by the logging console command.)

The message includes the access list name and sequence number, whether the packet was denied; the protocol, whether it was TCP, UDP, ICMP, or a number; and, if appropriate, the source and destination addresses and source and destination port numbers. The message is generated for the first packet that matches, and then at 5-minute intervals, including the number of packets denied in the prior 5-minute interval.

log-input

(Optional) Provides the same function as the log keyword, except that the logging message also includes the input interface.

ttl

(Optional) Turns on matching against time-to-life (TTL) value.

operator

(Optional) Operand that compares the source or destination ports of the specified protocol. Operands are lt (less than), gt (greater than), eq (equal), neq (not equal), and range (inclusive range).

ttl value [value1 ... value2]

(Optional) TTL value used for filtering. Range is 1 to 255.

If only value is specified, the match is against this value.

If both value1 and value2 are specified, the packet TTL is matched against the range of TTLs between value1 and value2 .

icmp-off

(Optional) Turns off ICMP generation for denied packets

icmp-type

(Optional) ICMP message type for filtering ICMP packets. ICMP packets can be filtered by ICMP message type. Range is 0 to 255.

icmp-code

(Optional) ICMP message code for filtering ICMP packets. ICMP packets that are filtered by ICMP message type can also be filtered by the ICMP message code. Range is 0 to 255.

established

(Optional) For the TCP protocol only: Indicates an established connection.

match-any

(Optional) For the TCP protocol only: Filters on any combination of TCP flags.

match-all

(Optional) For the TCP protocol only: Filters on all TCP flags.

+ | -

(Required) For the TCP protocol match-any , match-all : Prefix flag-name with + or - . Use the + flag-name argument to match packets with the TCP flag set. Use the - flag-name argument to match packets when the TCP flag is not set.

flag-name

(Optional) For the TCP protocol match-any , match-all . Flag names are: ack, fin, psh, rst, syn.

Command Default

No IPv6 access list is defined.

ICMP message generation is enabled by default.

Command Modes

IPv6 access list configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The deny (IPv6) command is similar to the deny (IPv4) command, except that it is IPv6-specific.

Use the deny (IPv6) command following the ipv6 access-list command to define the conditions under which a packet passes the access list.

Specifying ipv6 for the protocol argument matches against the IPv6 header of the packet.

By default, the first statement in an access list is number 10, and the subsequent statements are numbered in increments of 10.

You can add permit, deny, or remark statements to an existing access list without retyping the entire list. To add a new statement anywhere other than at the end of the list, create a new statement with an appropriate entry number that falls between two existing entry numbers to indicate where it belongs.

Both the source-ipv6-prefix/prefix-length and destination-ipv6-prefix/prefix-length arguments are used for traffic filtering (the source prefix filters traffic based upon the traffic source; the destination prefix filters traffic based upon the traffic destination).


Note


IPv6 prefix lists, not access lists, should be used for filtering routing protocol prefixes.


The fragments keyword is an option only if the operator [port | protocol-port ] arguments are not specified.

Task ID

Task ID

Operations

acl

read, write

Examples

The following example shows how to configure the IPv6 access list named toCISCO and applies the access list to outbound traffic on GigabitEthernet interface 0/2/0/2. Specifically, the first deny entry in the list keeps all packets that have a destination TCP port number greater than 5000 from exiting out of GigabitEthernet interface 0/2/0/2. The second deny entry in the list keeps all packets that have a source UDPo port number less than 5000 from exiting out of GigabitEthernet interface 0/2/0/2. The second deny entry also logs all matches to the console. The first permit entry in the list permits all ICMP packets to exit out of GigabitEthernet interface 0/2/0/2. The second permit entry in the list permits all other traffic to exit out of GigabitEthernet interface 0/2/0/2. The second permit entry is necessary because an implicit deny all condition is at the end of each IPv6 access list.


RP/0/RSP0/CPU0:router(config)# ipv6 access-list toCISCO
RP/0/RSP0/CPU0:router(config-ipv6-acl)# deny tcp any any gt 5000
RP/0/RSP0/CPU0:router(config-ipv6-acl)# deny ipv6 any lt 5000 any log
RP/0/RSP0/CPU0:router(config-ipv6-acl)# permit icmp any any
RP/0/RSP0/CPU0:router(config-ipv6-acl)# permit any any
RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/2/0/2
RP/0/RSP0/CPU0:router(config-if)# ipv6 access-group tOCISCO out

Related Commands

Command

Description

ipv6 access-list

Defines an IPv6 access list and enters IPv6 access list configuration mode.

permit (IPv6)

Sets permit conditions for an IPv6 access list.

remark (IPv6)

Inserts a helpful remark about an IPv6 access list entry.

resequence access-list ipv6

Changes the starting entry number of the first statement in an existing IPv6 access list, and the number by which subsequent statements are incremented.

ipv4 access-group

To control access to an interface, use the ipv4 access-group command in interface configuration mode. To remove the specified access group, use the no form of this command.

ipv4 access-group access-list-name { ingress | egress } [hardware-count] [interface-statistics]

no ipv4 access-group access-list-name { ingress | egress } [hardware-count] [interface-statistics]

Syntax Description

access-list-name

Name of an IPv4 access list as specified by an ipv4 access-list command.

ingress

Filters on inbound packets.

egress

Filters on outbound packets.

hardware-count

(Optional) Specifies to access a group’s hardware counters.

interface-statistics

(Optional) Specifies per-interface statistics in the hardware.

Command Default

The interface does not have an IPv4 access list applied to it.

Command Modes

Interface configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced .

Release 4.3.1

The common keyword was added.

Release 4.3.1

The compress level keyword was added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the ipv4 access-group command to control access to an interface. To remove the specified access group, use the no form of the command. Use the access-list-name argument to specify a particular IPv4 access list. Use theingress keyword to filter on inbound packets or theegress keyword to filter on outbound packets. Use the hardware-count argument to enable hardware counters for the access group.

Permitted packets are counted only when hardware counters are enabled using the hardware-count argument. Denied packets are counted whether hardware counters are enabled or not.


Note


For packet filtering applications using the ipv4 access-group command, packet counters are maintained in hardware for each direction. If an access group is used on multiple interfaces in the same direction, then packets are counted for each interface that has the hardware-count argument enabled.


If the access list permits the addresses, the software continues to process the packet. If the access list denies the address, the software discards the packet and returns an Internet Control Message Protocol (ICMP) host unreachable message.

If the specified access list does not exist, all packets are passed.

By default, the unique or per-interface ACL statistics are disabled.

Task ID

Task ID

Operations

acl

read, write

network

read, write

Examples

The following example shows how to apply filters on packets inbound and outbound from GigabitEthernet Packet-over-SONET (POS) interface 0/2/0/2:


RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/2/0/2
RP/0/RSP0/CPU0:router(config-if)# ipv4 access-group p-ingress-filter ingress
RP/0/RSP0/CPU0:router(config-if)# ipv4 access-group p-egress-filter egress

The following example shows how to apply per-interface statistics in the hardware:


RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/2/0/2
RP/0/RSP0/CPU0:router(config-if)# ipv4 access-group p-ingress-filter ingress interface-statistics

Related Commands

Command

Description

clear access-list ipv4

Resets the IPv4 access list match counters.

deny (IPv4)

Sets the deny conditions for an IPv4 access list.

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

permit (IPv4)

Sets the permit conditions for an IPv4 access list.

show access-lists ipv4

Displays the contents of all current IPv4 access lists.

show ipv4 interface

Displays the usability status of interfaces configured for IPv4.

ipv4 access-list

To define an IPv4 access list by name, use the ipv4 access-list command in global configuration mode. To remove all entries in an IPv4 access list, use the no form of this command.

ipv4 access-list name

no ipv4 access-list name

Syntax Description

name

Name of the access list. Names cannot contain a space or quotation marks.

Command Default

No IPv4 access list is defined.

Command Modes

Global configuration mode

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Release 4.3.0

This command was supported in BNG.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the ipv4 access-list command to configure an IPv4 access list. This command places the router in access list configuration mode, in which the denied or permitted access conditions must be defined with the deny or permit command.

Use the resequence access-list ipv4 command if you want to add a permit, deny, or remark statement between consecutive entries in an existing IPv4 access list. Specify the first entry number (the base) and the increment by which to separate the entry numbers of the statements. The software renumbers the existing statements, thereby making room to add new statements with the unused entry numbers.

Use the ipv4 access-group command to apply the access list to an interface.

Task ID

Task ID

Operations

acl

read, write

Examples

This example shows how to define a standard access list named Internetfilter:


RP/0/RSP0/CPU0:router(config)# ipv4 access-list Internetfilter
RP/0/RSP0/CPU0:router(config-if)# 10 permit 192.168.34.0 0.0.0.255
RP/0/RSP0/CPU0:router(config-if)# 20 permit 172.16.0.0 0.0.255.255
RP/0/RSP0/CPU0:router(config-if)# 30 permit 10.0.0.0 0.255.255.255
RP/0/RSP0/CPU0:router(config-if)# 39 remark Block BGP traffic from 172.16 net.
RP/0/RSP0/CPU0:router(config-if)# 40 deny tcp host 172.16.0.0 eq bgp host 192.168.202.203 range 1300 1400

ipv4 access-list log-update rate

To specify the rate at which IPv4 access lists are logged, use the ipv4 access-list log-update rate command in global configuration mode. To return the update rate to the default setting, use the no form of this command.

ipv4 access-list log-update rate rate-number

no ipv4 access-list log-update rate rate-number

Syntax Description

rate-number

Rate at which IPv4 access hit logs are generated per second on the router. Range is 1 to 1000.

Command Default

Default is 1.

Command Modes

Global configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The rate-number argument applies to all the IPv4 access-lists configured on the interfaces. That is, at any given time there can be between 1 and 1000 log entries for the system.

Task ID

Task ID

Operations

ipv4

read, write

acl

read, write

Examples

The following example shows how to configure a IPv4 access hit logging rate for the system:


RP/0/RSP0/CPU0:router(config)# ipv4 access-list log-update rate 10

ipv4 access-list log-update threshold

To specify the number of updates that are logged for IPv4 access lists, use the ipv4 access-list log-update threshold command in global configuration mode. To return the number of logged updates to the default setting, use the no form of this command.

ipv4 access-list log-update threshold update-number

no ipv4 access-list log-update threshold update-number

Syntax Description

update-number

Number of updates that are logged for every IPv4 access list configured on the router. Range is 0 to 2147483647.

Command Default

For IPv4 access lists, 2147483647 updates are logged.

Command Modes

Global configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

IPv4 access list updates are logged at 5-minute intervals, following the first logged update. Configuring a lower number of updates (a number lower than the default) is useful when more frequent update logging is desired.

Task ID

Task ID

Operations

basic-services

read, write

acl

read, write

Examples

The following example shows how to configure a log threshold of ten updates for every IPv4 access list configured on the router:


RP/0/RSP0/CPU0:router(config)# ipv4 access-list log-update threshold 10

Related Commands

Command

Description

deny (IPv4)

Sets the deny conditions for an IPv4 access list.

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

permit (IPv4)

Sets the permit conditions for an IPv4 access list.

show access-lists ipv4

Displays the contents of all current IPv4 access lists.

ipv6 access-group

To control access to an interface, use the ipv6 access-group command in interface configuration mode. To remove the specified access group, use the no form of this command.

ipv6 access-groupaccess-list-name { ingress | egress } [interface-statistics]

no ipv6 access-group access-list-name { ingress | egress } [interface-statistics]

Syntax Description

access-list-name

Name of an IPv6 access list as specified by an ipv6 access-list command.

ingress

Filters on inbound packets.

egress

Filters on outbound packets.

interface-statistics

(Optional) Specifies per-interface statistics in the hardware.

Command Default

The interface does not have an IPv6 access list applied to it.

Command Modes

Interface configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Release 4.3.0

Support for IPv6 ACL on L2 transport interface was added.

Release 4.3.1

The common keyword was added.

Release 4.3.1

The compress level keyword was added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The ipv6 access-group command is similar to the ipv4 access-group command, except that it is IPv6-specific.

Use the ipv6 access-group command to control access to an interface. To remove the specified access group, use the no form of the command. Use the access-list-name to specify a particular IPv6 access list. Use theingress keyword to filter on inbound packets or the egress keyword to filter on outbound packets.


Note


For packet filtering applications using the ipv6 access-group command, packet counters are maintained in hardware for each direction. If an access group is used on multiple interfaces in the same direction, then packets are counted for each interface.


If the access list permits the addresses, the software continues to process the packet. If the access list denies the address, the software discards the packet and returns a rate-limited Internet Control Message Protocol (ICMP) host unreachable message.

If the specified access list does not exist, all packets are passed.

By default, the unique or per-interface ACL statistics are disabled.

Task ID

Task ID

Operations

acl

read, write

ipv6

read, write

Examples

This example shows how to apply filters on packets inbound and outbound from GigabitEthernet interface 0/2/0/2:

RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/2/0/2
RP/0/RSP0/CPU0:router(config-if)# ipv6 access-group p-in-filter ingress
RP/0/RSP0/CPU0:router(config-if)# ipv6 access-group p-out-filter egress

This example shows how to apply per-interface statistics in the hardware:

RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/2/0/2
RP/0/RSP0/CPU0:router(config-if)# ipv6 access-group p-in-filter ingress interface-statistics

ipv6 access-list

To define an IPv6 access list and to place the router in IPv6 access list configuration mode, use the ipv6 access-list command in global configuration mode. To remove the access list, use the no form of this command.

ipv6 access-list name

no ipv6 access-list name

Syntax Description

name

Name of the IPv6 access list. Names cannot contain a space or quotation mark, or begin with a numeric.

Command Default

No IPv6 access list is defined.

Command Modes

Global configuration mode

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Release 4.3.0

Support for IPv6 ACL on L2 transport interface was added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The ipv6 access-list command is similar to the ipv4 access-list command, except that it is IPv6-specific.

The IPv6 access lists are used for traffic filtering based on source and destination addresses, IPv6 option headers, and optional, upper-layer protocol type information for finer granularity of control. IPv6 access lists are defined by using the ipv6 access-list command in global configuration mode and their permit and deny conditions are set by using the deny and permit commands in IPv6 access list configuration mode. Configuring the ipv6 access-list command places the router in IPv6 access list configuration mode—the router prompt changes to router (config-ipv6-acl)#. From IPv6 access list configuration mode, permit and deny conditions can be set for the defined IPv6 access list.

See the “Examples” section for an example of a translated IPv6 access control list (ACL) configuration.


Note


No more than one IPv6 access list can be applied to an interface per direction.



Note


Every IPv6 access list has an implicit deny ipv6 any any statement as its last match condition. An IPv6 access list must contain at least one entry for the implicit deny ipv6 any any statement to take effect.



Note


IPv6 prefix lists, not access lists, should be used for filtering routing protocol prefixes.


Use the ipv6 access-group interface configuration command with the access-list-name argument to apply an IPv6 access list to an IPv6 interface.


Note


An IPv6 access list applied to an interface with the ipv6 access-group command filters traffic that is forwarded, not originated, by the router.



Note


Every IPv6 ACL has implicit permit icmp any any nd-na, permit icmp any any nd-ns, and deny ipv6 any any statements as its last match conditions. (The former two match conditions allow for ICMPv6 neighbor discovery.) An IPv6 ACL must contain at least one entry for the implicit deny ipv6 any any statement to take effect.permit icmp any any nd-na permit icmp any any nd-ns deny ipv6 any any deny ipv6 any any.


The IPv6 neighbor discovery process makes use of the IPv6 network layer service; therefore, by default, IPv6 ACLs implicitly allow IPv6 neighbor discovery packets to be sent and received on an interface. In IPv4, the Address Resolution Protocol (ARP), which is equivalent to the IPv6 neighbor discovery process, makes use of a separate data link layer protocol; therefore, by default, IPv4 ACLs implicitly allow ARP packets to be sent and received on an interface.

Task ID

Task ID

Operations

acl

read, write

ipv6

read, write

Examples

This example shows how to configure the IPv6 access list named list2 and applies the ACL to outbound traffic on interface GigabitEthernet 0/2/0/2. Specifically, the first ACL entry keeps all packets from the network fec0:0:0:2::/64 (packets that have the site-local prefix fec0:0:0:2 as the first 64 bits of their source IPv6 address) from exiting out of interface GigabitEthernet 0/2/0/2. The second entry in the ACL permits all other traffic to exit out of interface GigabitEthernet 0/2/0/2. The second entry is necessary because an implicit deny all condition is at the end of each IPv6 ACL.

RP/0/RSP0/CPU0:router(config)# ipv6 access-list list2
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 10 deny fec0:0:0:2::/64 any
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 20 permit any any

RP/0/RSP0/CPU0:router# show ipv6 access-lists list2

ipv6 access-list list2
  10 deny ipv6 fec0:0:0:2::/64 any
  20 permit ipv6 any any

RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/2/0/2
RP/0/RSP0/CPU0:router(config-if)# ipv6 access-group list2 egress

Note


IPv6 is automatically configured as the protocol type in permit any any and deny any any statements that are translated from global configuration mode to IPv6 access list configuration mode.



Note


An IPv6 router does not forward to another network an IPv6 packet that has a link-local address as either its source or destination address (and the source interface for the packet is different from the destination interface for the packet).


ipv6 access-list log-update rate

To specify the rate at which IPv6 access lists are logged, use the ipv6 access-list log-update rate command in global configuration mode. To return the update rate to the default setting, use the no form of this command.

ipv6 access-list log-update rate rate-number

no ipv6 access-list log-update rate rate-number

Syntax Description

rate-number

Rate at which IPv6 access hit logs are generated per second on the router. Range is 1 to 1000.

Command Default

Default is 1.

Command Modes

Global configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The rate-number argument applies to all the IPv6 access-lists configured on the interfaces. That is, at any given time there can be between 1 and 1000 log entries for the system.

Task ID

Task ID

Operations

ipv6

read, write

acl

read, write

Examples

The following example shows how to configure a IPv6 access hit logging rate for the system:

RP/0/RSP0/CPU0:router(config)# ipv6 access-list log-update rate 10

ipv6 access-list log-update threshold

To specify the number of updates that are logged for IPv6 access lists (ACLs), use the ipv6 access-list log-update threshold command in global configuration mode. To return the number of logged updates to the default setting, use the no form of this command.

ipv6 access-list log-update threshold update-number

no ipv6 access-list log-update threshold update-number

Syntax Description

update-number

Number of updates that are logged for every IPv6 access list configured on the router. Range is 0 to 2147483647.

Command Default

For IPv6 access lists, 350000 updates are logged.

Command Modes

Global configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The ipv6 access-list log-update threshold command is similar to the ipv4 access-list log-update threshold command, except that it is IPv6-specific.

IPv6 access list updates are logged at 5-minute intervals, following the first logged update. Configuring a lower number of updates (a number lower than the default) is useful when more frequent update logging is desired.

Task ID

Task ID

Operations

acl

read, write

ipv6

read, write

Examples

The following example shows how to configure a log threshold of ten updates for every IPv6 access list configured on the router:

RP/0/RSP0/CPU0:router(config)# ipv6 access-list log-update threshold 10

ipv6 access-list maximum ace threshold

To set the maximum number of access control entries (ACEs) for IPv6 access lists, use the ipv6 access-list maximum ace threshold command in global configuration mode. To reset the ACE limit for IPv6 access lists, use the no form of this command.

ipv6 access-list maximum ace threshold ace-number

no ipv6 access-list maximum ace threshold ace-number

Syntax Description

ace-number

Maximum number of configurable ACEs allowed. Range is 50000 to 350000.

Command Default

50,000 ACEs are allowed for IPv6 access lists.

Command Modes

Global configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the ipv6 access-list maximum ace threshold command to set the maximum number of configurable ACEs for IPv6 access lists. Out of resource (OOR) limits the number of ACEs that can be configured in the system. When the maximum number of configurable ACEs is reached, configuration of new ACEs is rejected.

Task ID

Task ID

Operations

acl

read, write

ipv6

read, write

Examples

The following example shows how to set the maximum number of ACEs for IPv6 access lists to 75000:

RP/0/RSP0/CPU0:router(config)# ipv6 access-list maximum ace threshold 75000

Related Commands

Command

Description

show access-lists ipv6

Displays the contents of all current IPv6 access lists.

ipv6 access-list maximum acl threshold

To set the maximum number of configurable IPv6 access control lists (ACLs), use the ipv6 access-list maximum acl threshold command in global configuration mode. To reset the IPv6 ACL limit, use the no form of this command.

ipv6 access-list maximum acl threshold acl-number

no ipv6 access-list maximum ace threshold acl-number

Syntax Description

acl-number

Maximum number of configurable ACLs allowed. Range is 1000 to 16000.

Command Default

1000 IPv6 ACLs can be configured.

Command Modes

Global configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the ipv6 access-list maximum acl threshold command to set the maximum number of configurable IPv6 ACLs. Out of resource (OOR) limits the number of ACLs that can be configured in the system. When the limit is reached, configuration of new ACLs is rejected.

Task ID

Task ID

Operations

acl

read, write

ipv6

read, write

Examples

The following example shows how to set the maximum number of configurable IPv6 ACLs to 1500:

RP/0/RSP0/CPU0:router(config)# ipv6 access-list maximum acl threshold 1500

Related Commands

Command

Description

show access-lists ipv6

Displays the contents of all current IPv6 access lists.

permit (IPv4)

To set conditions for an IPv4 access list, use the permit command in access list configuration mode. There are two versions of the permit command: permit (source), and permit (protocol). To remove a condition from an access list, use the no form of this command.

[sequence-number] permit source [source-wildcard] [ log | log-input ]

[sequence-number] permit protocol source source-wildcard destination destination-wildcard [capture] [ precedence precedence ] [ default nexthop [ipv4-address1] [ipv4-address2] [ipv4-address3] ] [ dscp dscp ] [fragments] [ log | log-input ] [ nexthop [ track track-name ] [ipv4-address1] [ipv4-address2] [ipv4-address3] ] [ ttl ttl value [ value1 . .. value2 ] ]

no sequence-number

Internet Control Message Protocol (ICMP)

[sequence-number] permit icmp source source-wildcard destination destination-wildcard [icmp-type] [icmp-code] [ precedence precedence ] [ dscp dscp ] [fragments] [ log | log-input ] [icmp-off]

Internet Group Management Protocol (IGMP)

[sequence-number] permit igmp source source-wildcard destination destination-wildcard [igmp-type] [ precedence precedence ] [ dscp value ] [fragments] [ log | log-input ]

User Datagram Protocol (UDP)

[sequence-number] permit udp source source-wildcard [ operator { port | protocol-port } ] destination destination-wildcard [ operator { port | protocol-port } ] [ precedence precedence ] [ dscp dscp ] [fragments] [ log | log-input ]

Syntax Description

sequence-number

(Optional) Number of the permit statement in the access list. This number determines the order of the statements in the access list. Range is 1 to 2147483644. (By default, the first statement is number 10, and the subsequent statements are incremented by 10.) Use the resequence access-list command to change the number of the first statement and increment subsequent statements of a configured access list.

source

Number of the network or host from which the packet is being sent. There are three alternative ways to specify the source:

  • Use a 32-bit quantity in four-part dotted-decimal format.
  • Use the any keyword as an abbreviation for a source and source-wildcard of 0.0.0.0 255.255.255.255.
  • Use the host source combination as an abbreviation for a source and source-wildcard of source 0.0.0.0.

source-wildcard

Wildcard bits to be applied to the source. There are three alternative ways to specify the source wildcard:

  • Use a 32-bit quantity in four-part dotted-decimal format. Place ones in the bit positions you want to ignore.
  • Use the any keyword as an abbreviation for a source and source-wildcard of 0.0.0.0 255.255.255.255.
  • Use the host source combination as an abbreviation for a source and source-wildcard of source 0.0.0.0.

protocol

Name or number of an IP protocol. It can be one of the keywords ahp , esp , eigrp , gre , icmp , igmp , igrp , ip , ipinip , nos , ospf , pim , pcp , tcp , or udp , or an integer from 0 to 255 representing an IP protocol number. To match any Internet protocol (including ICMP, TCP, and UDP), use the ip keyword. ICMP, and TCP allow further qualifiers, which are described later in this table.

destination

Number of the network or host to which the packet is being sent. There are three alternative ways to specify the destination:

  • Use a 32-bit quantity in four-part dotted-decimal format.
  • Use the any keyword as an abbreviation for the destination and destination-wildcard of 0.0.0.0 255.255.255.255.
  • Use the host destination combination as an abbreviation for a destination and destination-wildcard of destination 0.0.0.0.

destination-wildcard

Wildcard bits to be applied to the destination. There are three alternative ways to specify the destination wildcard:

  • Use a 32-bit quantity in four-part dotted-decimal format. Place ones in the bit positions you want to ignore.
  • Use the any keyword as an abbreviation for a destination and destination-wildcard of 0.0.0.0 255.255.255.255.
  • Use the host destination combination as an abbreviation for a destination and destination-wildcard of destination 0.0.0.0.

precedence precedence

(Optional) Packets can be filtered by precedence level (as specified by a number from 0 to 7) or by the following names:

  • Routine —Match packets with routine precedence (0)
  • priority —Match packets with priority precedence (1)
  • immediate —Match packets with immediate precedence (2)
  • flash —Match packets with flash precedence (3)
  • flash-override —Match packets with flash override precedence (4)
  • critical —Match packets with critical precedence (5)
  • internet —Match packets with internetwork control precedence (6)
  • network —Match packets with network control precedence (7)

default

(Optional) Specifies the default next hop for this entry.

If the default keyword is configured, ACL-based forwarding action is taken only if the results of the PLU lookup for the destination of the packets determine a default route; that is, no specified route is determined to the destination of the packet.

capture

Captures matching traffic.

When the acl command is configured on the source mirroring port, if the ACL configuration command does not use the capture keyword, no traffic gets mirrored. If the ACL configuration uses the capture keyword, but the acl command is not configured on the source port, then the whole port traffic is mirrored and the capture action does not have any affect.

ipv4-address1 ipv4-address2 ipv4-address3

(Optional) Uses one to three next-hop addresses. The IP address types are defined as follows:

  • Default IP addresses—Specifies the next-hop router in the path toward the destination in which the packets must be forwarded, if there is no explicit route for the destination address of the packet in the routing table. The first IP address that is associated with a connected interface that is currently up is used to route the packets.
  • Specified IP addresses—Specifies the next-hop router in the path toward the destination in which the packets must be forwarded. The first IP address that is associated with a connected interface that is currently up is used to route the packets.

dscp dscp

(Optional) Differentiated services code point (DSCP) provides quality of service control. The values for dscp are as follows:

  • 0–63—Differentiated services codepoint value
  • af11—Match packets with AF11 dscp (001010)
  • af12—Match packets with AF12 dscp (001100)
  • af13—Match packets with AF13 dscp (001110)
  • af21—Match packets with AF21 dscp (010010)
  • af22—Match packets with AF22 dscp (010100)
  • af23—Match packets with AF23 dscp (010110)
  • af31—Match packets with AF31 dscp (011010)
  • af32—Match packets with AF32 dscp (011100)
  • af33—Match packets with AF33 dscp (011110)
  • af41—Match packets with AF41 dscp (100010)
  • af42—Match packets with AF42 dscp (100100)
  • af43–Match packets with AF43 dscp (100110)
  • cs1—Match packets with CS1 (precedence 1) dscp (001000)
  • cs2—Match packets with CS2 (precedence 2) dscp (010000)
  • cs3—Match packets with CS3 (precedence 3) dscp (011000)
  • cs4—Match packets with CS4 (precedence 4) dscp (100000)
  • cs5—Match packets with CS5 (precedence 5) dscp (101000)
  • cs6—Match packets with CS6 (precedence 6) dscp (110000)
  • cs7—Match packets with CS7 (precedence 7) dscp (111000)
  • default—Default DSCP (000000)
  • ef—Match packets with EF dscp (101110)

fragments

(Optional) Causes the software to examine noninitial fragments of IPv4 packets when applying this access list entry. When this keyword is specified, fragments are subject to the access list entry.

log

(Optional) Causes an informational logging message about the packet that matches the entry to be sent to the console. (The level of messages logged to the console is controlled by the logging console command.)

The message includes the access list number, whether the packet was permitted or denied; the protocol, whether it was TCP, UDP, ICMP, or a number; and, if appropriate, the source and destination addresses and source and destination port numbers. The message is generated for the first packet that matches a flow, and then at 5-minute intervals, including the number of packets permitted or denied in the prior 5-minute interval.

log-input

(Optional) Provides the same function as the log keyword, except that the logging message also includes the input interface.

nexthop1, nexthop2, nexthop3

(Optional) Forwards the specified next hop for this entry.

track track-name

Specifies the TRACK Name for this nexthop.

ttl

(Optional) Turns on matching against time-to-life (TTL) value.

ttl value [value1 ... value2]

(Optional) TTL value used for filtering. Range is 1 to 255.

If only value is specified, the match is against this value.

If both value1 and value2 are specified, the packet TTL is matched against the range of TTLs between value1 and value2 .

icmp-off

(Optional) Turns off ICMP generation for denied packets

icmp-type

(Optional) ICMP message type for filtering ICMP packets. Range is from 0 to 255.

icmp-code

(Optional) ICMP message code for filtering ICMP packets. Range is from 0 to 255.

igmp-type

(Optional) IGMP message type (0 to 15) or message name for filtering IGMP packets, as follows:

  • dvmrp
  • host-query
  • host-report
  • mtrace
  • mtrace-response
  • pim
  • precedence
  • trace
  • v2-leave
  • v2-report
  • v3-report

operator

(Optional) Operator is used to compare source or destination ports. Possible operands are lt (less than), gt (greater than), eq (equal), neq (not equal), and range (inclusive range).

If the operator is positioned after the source and source-wildcard values, it must match the source port.

If the operator is positioned after the destination and destination-wildcard values, it must match the destination port.

If the operator is positioned after the ttl keyword, it matches the TTL value.

The range operator requires two port numbers. All other operators require one port number.

port

Decimal number a TCP or UDP port. Range is 0 to 65535.

TCP ports can be used only when filtering TCP. UDP ports can be used only when filtering UDP.

protocol-port

Name of a TCP or UDP port. TCP and UDP port names are listed in the “Usage Guidelines” section.

TCP port names can be used only when filtering TCP. UDP port names can be used only when filtering UDP.

established

(Optional) For the TCP protocol only: Indicates an established connection.

match-any

(Optional) For the TCP protocol only: Filters on any combination of TCP flags.

match-all

(Optional) For the TCP protocol only: Filters on all TCP flags.

+ | -

(Required) For the TCP protocol match-any , match-all : Prefix flag-name with + or - . Use the + flag-name argument to match packets with the TCP flag set. Use the - flag-name argument to match packets when the TCP flag is not set.

flag-name

(Optional) For the TCP protocol match-any , match-all . Flag names are: ack , fin , psh , rst , syn .

Command Default

There is no specific condition under which a packet is denied passing the IPv4 access list.

ICMP message generation is enabled by default.

Command Modes

IPv4 access list configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Release 4.0.1

The capture keyword was added.

Release 4.3.1

The range keyword for dscp and net-group and port-group keywords were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the permit command following the ipv4 access-list command to specify conditions under which a packet can pass the access list.

By default, the first statement in an access list is number 10, and the subsequent statements are incremented by 10.

You can add permit, deny, or remark statements to an existing access list without retyping the entire list. To add a new statement anywhere other than at the end of the list, create a new statement with an appropriate entry number that falls between two existing entry numbers to indicate where it belongs.

If you want to add a statement between two consecutively numbered statements (for example, between lines 10 and 11), first use the resequence access-list command to renumber the first statement and increment the entry number of each subsequent statement. The increment argument causes new, unused line numbers between statements. Then add a new statement with the entry-number specifying where it belongs in the access list.

The following is a list of precedence names:

  • critical
  • flash
  • flash-override
  • immediate
  • internet
  • network
  • priority
  • routine

The following is a list of ICMP message type names:

  • administratively-prohibited
  • alternate-address
  • conversion-error
  • dod-host-prohibited
  • dod-net-prohibited
  • echo
  • echo-reply
  • general-parameter-problem
  • host-isolated
  • host-precedence-unreachable
  • host-redirect
  • host-tos-redirect
  • host-tos-unreachable
  • host-unknown
  • host-unreachable
  • information-reply
  • information-request
  • mask-reply
  • mask-request
  • mobile-redirect
  • net-redirect
  • net-tos-redirect
  • net-tos-unreachable
  • net-unreachable
  • network-unknown
  • no-room-for-option
  • option-missing
  • packet-too-big
  • parameter-problem
  • port-unreachable
  • precedence-unreachable
  • protocol-unreachable
  • reassembly-timeout
  • redirect
  • router-advertisement
  • router-solicitation
  • source-quench
  • source-route-failed
  • time-exceeded
  • timestamp-reply
  • timestamp-request
  • traceroute
  • ttl-exceeded
  • unreachable

The following is a list of TCP port names that can be used instead of port numbers. Refer to the current Assigned Numbers RFC to find a reference to these protocols. You can find port numbers corresponding to these protocols by typing a ? in the place of a port number.

  • bgp
  • chargen
  • cmd
  • daytime
  • discard
  • domain
  • echo
  • exec
  • finger
  • ftp
  • ftp-data
  • gopher
  • hostname
  • ident
  • irc
  • klogin
  • kshell
  • login
  • lpd
  • nntp
  • pim-auto-rp
  • pop2
  • pop3
  • smtp
  • sunrpc
  • tacacs
  • talk
  • telnet
  • time
  • uucp
  • whois
  • www

The following UDP port names can be used instead of port numbers. Refer to the current Assigned Numbers RFC to find a reference to these protocols. You can find port numbers corresponding to these protocols by typing a ? in the place of a port number.

  • biff
  • bootpc
  • bootps
  • discard
  • dnsix
  • domain
  • echo
  • isakmp
  • mobile-ip
  • nameserver
  • netbios-dgm
  • netbios-ns
  • netbios-ss
  • ntp
  • pim-auto-rp
  • rip
  • snmp
  • snmptrap
  • sunrpc
  • syslog
  • tacacs
  • talk
  • tftp
  • time
  • who
  • xdmcp

Use the following flags in conjunction with the match-any and match-all keywords and the + and - signs to select the flags to display:

For example, match-all +ack +syn displays TCP packets with both the ack and syn flags set, or match-any +ack syn displays the TCP packets with the ack set or the syn not set.

Task ID

Task ID

Operations

ipv4

read, write

acl

read, write

Examples

The following example shows how to set a permit condition for an access list named Internetfilter:

RP/0/RSP0/CPU0:router(config)# ipv4 access-list Internetfilter
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 10 permit 192.168.34.0 0.0.0.255
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 20 permit 172.16.0.0 0.0.255.255
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 25 permit tcp host 172.16.0.0 eq bgp host 192.168.202.203 range 1300 1400
RP/0/RSP0/CPU0:router(config-ipv4-acl)# deny 10.0.0.0 0.255.255.255


Related Commands

Command

Description

deny (IPv4)

Sets the conditions for an IPv4 access list.

ipv4 access-group

Filters incoming or outgoing IPv4 traffic on an interface.

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

remark (IPv4)

Inserts a helpful remark about an IPv4 access list entry.

resequence access-list ipv4

Changes the starting entry number of the first statement in an existing IPv4 access list, and the number by which subsequent statements are incremented.

show access-lists ipv4

Displays the contents of all current IPv4 access lists.

permit (IPv6)

To set permit conditions for an IPv6 access list, use the permit command in IPv6 access list configuration mode. To remove the permit conditions, use the no form of this command.

[sequence-number] permit protocol { source-ipv6-prefix/ prefix-length | any | host source-ipv6-address } [ operator { port | protocol-port } capture ] [ dscp value] [ routing] [ authen] [ destopts] [ fragments] [ packet-length operator packet-length value ] [ log | log-input] [ ttl operator ttl value ]

no sequence-number

Internet Control Message Protocol (ICMP)

[ sequence-number] permit icmp { source-ipv6-prefix/ prefix-length | any | host source-ipv6-address } { destination-ipv6-prefix/ prefix-length | any | host destination-ipv6-address } [ icmp-type] [ icmp-code][ dscp value] [ routing] [ authen] [ destopts] [ fragments] [ log] [ log-input] [ icmp-off]

Transmission Control Protocol (TCP)

[sequence-number] permit tcp { source-ipv6-prefix/ prefix-length | any | host source-ipv6-address } [ operator { port | protocol-port } ] { destination-ipv6-prefix/ prefix-length | any | host destination-ipv6-address } [ operator { port | protocol | port } ] [ dscp value] [ routing] [ authen] [ destopts] [ fragments] [ established] { match-any | match-all | + | - } [ flag-name] [ log] [ log-input]

User Datagram Protocol (UDP)

[sequence-number] permit tcp { source-ipv6-prefix/ prefix-length | any | host source-ipv6-address } [ operator { port | protocol-port } ] { destination-ipv6-prefix/ prefix-length | any | host destination-ipv6-address } [ operator { port | protocol | port } ] [ dscp value] [ routing] [ authen] [ destopts] [ fragments] [ established] [ flag-name] [ log] [ log-input]

Syntax Description

sequence-number

(Optional) Number of the permit statement in the access list. This number determines the order of the statements in the access list. Range is from 1 to 2147483644. (By default, the first statement is number 10, and the subsequent statements are incremented by 10.) Use the resequence access-list command to change the number of the first statement and increment subsequent statements of a configured access list.

protocol

Name or number of an Internet protocol. It can be one of the keywords ahp, eigrp, esp, gre, icmp, igmp, igrp, isinip, ipv6, nos, ospf, pcp, sctp, tcp, or udp, or an integer that ranges from 0 to 255, representing an IPv6 protocol number.

source-ipv6-prefix / prefix-length

Source IPv6 network or class of networks about which permit conditions are to be set.

This argument must be in the form documented in RFC 2373, where the address is specified in hexadecimal using 16-bit values between colons.

any

An abbreviation for the IPv6 prefix ::/0.

capture

Captures matching traffic.

When the acl command is configured on the source mirroring port, if the ACL configuration command does not use the capture keyword, no traffic gets mirrored. If the ACL configuration uses the capture keyword, but the acl command is not configured on the source port, then the whole port traffic is mirrored and the capture action does not have any effect.

host source-ipv6-address

Source IPv6 host address about which to set permit conditions.

This source-ipv6-address argument must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.

operator {port | protocol-port}

(Optional) Operand that compares the source or destination ports of the specified protocol. Operands are lt (less than), gt (greater than), eq (equal), neq (not equal), and range (inclusive range).

If the operator is positioned after the source-ipv6-prefix / prefix-length argument, it must match the source port.

If the operator is positioned after the destination-ipv6-prefix / prefix-length argument, it must match the destination port.

The range operator requires two port numbers. All other operators require one port number.

The port argument is the decimal number of a TCP or UDP port. A port number is a number whose range is from 0 to 65535. The protocol-port argument is the name of a TCP or UDP port. TCP port names can be used only when filtering TCP. UDP port names can be used only when filtering UDP.

destination-ipv6-prefix / prefix-length

Destination IPv6 network or class of networks about which permit conditions are to be set.

This argument must be in the form documented in RFC 2373, where the address is specified in hexadecimal using 16-bit values between colons.

host destination-ipv6-address

Specifies the destination IPv6 host address about which permit conditions are to be set.

This destination-ipv6-address argument must be in the form documented in RFC 2373, where the address is specified in hexadecimal using 16-bit values between colons.

dscp value

(Optional) Matches a differentiated services code point (DSCP) value against the traffic class value in the Traffic Class field of each IPv6 packet header. Range is from 0 to 63.

routing

(Optional) Matches source-routed packets against the routing extension header within each IPv6 packet header.

authen

(Optional) Matches if the IPv6 authentication header is present.

destopts

(Optional) Matches if the IPv6 destination options header is present.

fragments

(Optional) Matches noninitial fragmented packets where the fragment extension header contains a nonzero fragment offset. The fragments keyword is an option available only if the operator [ port-number ] arguments are not specified.

log

(Optional) Causes an informational logging message about the packet that matches the entry to be sent to the console. (The level of messages logged to the console is controlled by the logging console command.)

The message includes the access list name and sequence number, and whether the packet is permitted; the protocol, and whether it is TCP, UDP, ICMP, or a number; and, if appropriate, the source and destination addresses and source and destination port numbers. The message is generated for the first matching packet, and then at 5-minute intervals, including the number of packets permitted in the prior 5-minute interval.

log-input

(Optional) Provides the same function as the log keyword, however, the logging message also includes the input interface.

ttl

(Optional) Turns on matching against time-to-live (TTL) value.

operator

(Optional) Operand that compares the source or destination ports of the specified protocol. Operands are lt (less than), gt (greater than), eq (equal), neq (not equal), and range (inclusive range).

ttl value [value1 value2]

(Optional) TTL value used for filtering. Range is from 1 to 255.

If only value is specified, the match is against this value.

If both value1 and value2 are specified, the packet TTL is matched against the range of TTLs between value1 and value2 .

icmp-off

(Optional) Turns off ICMP generation for denied packets.

icmp-type

(Optional) ICMP message type for filtering ICMP packets. Range is from 0 to 255.

icmp-code

(Optional) ICMP message code for filtering ICMP packets. Range is from 0 to 255.

established

(Optional) For the TCP protocol only: Indicates an established connection.

match-any

(Optional) For the TCP protocol only: Filters on any combination of TCP flags.

match-all

(Optional) For the TCP protocol only: Filters on all TCP flags.

+ | -

(Required) For the TCP protocol match-any , match-all : Prefix flag-name with + or - . Use the + flag-name argument to match packets with the TCP flag set. Use the - flag-name argument to match packets when the TCP flag is not set.

flag-name

(Required) For the TCP protocol match-any, match-all. Flag names are: ack, fin, psh, rst, syn.

Command Default

No IPv6 access list is defined.

ICMP message generation is enabled by default.

Command Modes

IPv6 access list configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Release 4.0.1

The capture keyword was added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The permit (IPv6) command is similar to the permit (IPv4) command, except that it is IPv6-specific.

Use the permit (IPv6) command following the ipv6 access-list command to define the conditions under which a packet passes the access list.

Specifying ipv6 for the protocol argument matches against the IPv6 header of the packet.

By default, the first statement in an access list is number 10, and the subsequent statements are numbered in increments of 10.

You can add permit, deny, or remark statements to an existing access list without retyping the entire list. To add a new statement anywhere other than the end of the list, create a new statement with an appropriate entry number that falls between two existing entry numbers to indicate where it belongs.

Both the source-ipv6-prefix/prefix-length and destination-ipv6-prefix/prefix-length arguments are used for traffic filtering (the source prefix filters traffic based upon the traffic source; the destination prefix filters traffic based upon the traffic destination).


Note


IPv6 prefix lists, and not access lists, should be used for filtering routing protocol prefixes.


The fragments keyword is an option available only if the operator [port | protocol-port] arguments are not specified.

Task ID

Task ID

Operations

acl

read, write

Examples

This example shows how to configure the IPv6 access list named toCISCO and applies the access list to outbound traffic on GigabitEthernet interface 0/2/0/2. Specifically, the first deny entry in the list keeps all packets that have a destination TCP port number greater than 5000 from exiting out of GigabitEthernet interface 0/2/0/2. The second deny entry in the list keeps all packets that have a source UDP port number less than 5000 from exiting out of GigabitEthernet interface 0/2/0/2. The second deny entry also logs all matches to the console. The first permit entry in the list permits all ICMP packets to exit out of GigabitEthernet interface 0/2/0/2. The second permit entry in the list permits all other traffic to exit out of GigabitEthernet interface 0/2/0/2. The second permit entry is necessary because an implicit deny all condition is at the end of each IPv6 access list.

RP/0/RSP0/CPU0:router(config)# ipv6 access-list toCISCO
RP/0/RSP0/CPU0:router(config-ipv6-acl)# deny tcp any any gt 5000
RP/0/RSP0/CPU0:router(config-ipv6-acl)# deny ipv6 any lt 5000 any log
RP/0/RSP0/CPU0:router(config-ipv6-acl)# permit icmp any any
RP/0/RSP0/CPU0:router(config-ipv6-acl)# permit any any
RP/0/RSP0/CPU0:router(config)# interface gigabitethernet 0/2/0/2
RP/0/RSP0/CPU0:router(config-if)# ipv6 access-group tOCISCO out

Related Commands

Command

Description

deny (IPv6)

Sets deny conditions for an IPv6 access list.

ipv6 access-list

Defines an IPv6 access list and enters IPv6 access list configuration mode.

remark (IPv6)

Inserts a helpful remark about an IPv6 access list entry.

resequence access-list ipv6

Changes the starting entry number of the first statement in an existing IPv6 access list, and the number by which subsequent statements are incremented.

remark (IPv4)

To write a helpful comment (remark) for an entry in an IPv4 access list, use the remark command in IPv4 access list configuration mode. To remove the remark, use the no form of this command.

[sequence-number] remark remark

no sequence-number

Syntax Description

sequence-number

(Optional) Number of the remark statement in the access list. This number determines the order of the statements in the access list. Range is 1 to 2147483646. (By default, the first statement is number 10; subsequent statements are incremented by 10.)

remark

Comment that describes the entry in the access list, up to 255 characters long.

Command Default

The IPv4 access list entries have no remarks.

Command Modes

IPv4 access list configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the remark command to write a helpful comment for an entry in an IPv4 access list. To remove the remark, use the no form of this command.

The remark can be up to 255 characters; anything longer is truncated.

If you know the sequence number of the remark you want to delete, you can remove it by entering the no  sequence-number command.

Use the resequence access-list ipv4 command if you want to add statements to an existing access list and the sequence numbers of consecutive entries do not permit additional statements.

Task ID

Task ID

Operations

ipv4

read, write

acl

read, write

Examples

In the following example, the user1 subnet is not allowed to use outbound Telnet:

RP/0/RSP0/CPU0:router(config)# ipv4 access-list telnetting
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 10 remark Do not allow user1 to telnet out
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 20 deny tcp host 172.16.2.88 255.255.0.0 any eq telnet
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 30 permit icmp any any
RP/0/RSP0/CPU0:router# show ipv4 access-list telnetting

ipv4 access-list telnetting
  0 remark Do not allow user1 to telnet out
  20 deny tcp 172.16.2.88 255.255.0.0 any eq telnet out
  30 permit icmp any any

Related Commands

Command

Description

deny (IPv4)

Sets the deny conditions for an IPv4 access list.

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

permit (IPv4)

Sets the permit conditions for an IPv4 access list

resequence access-list ipv4

Changes the starting entry number of the first statement in an existing IPv4 access list, and the number by which subsequent statements are incremented.

show access-lists ipv4

Displays the contents of all current IPv4 access lists.

remark (IPv6)

To write a helpful comment (remark) for an entry in an IPv6 access list, use the remark command in IPv6 access list configuration mode. To remove the remark, use the no form of this command.

[sequence-number] remark remark

no sequence-number

Syntax Description

sequence-number

(Optional) Number of the remark statement in the access list. This number determines the order of the statements in the access list. Range is 1 to 2147483646. (By default, the first statement is number 10, and the subsequent statements are incremented by 10.)

remark

Comment that describes the entry in the access list, up to 255 characters long.

Command Default

The IPv6 access list entries have no remarks.

Command Modes

IPv6 access list configuration

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The remark (IPv6) command is similar to the remark (IPv4) command, except that it is IPv6-specific.

Use the remark command to write a helpful comment for an entry in an IPv6 access list. To remove the remark, use the no form of this command.

The remark can be up to 255 characters; anything longer is truncated.

If you know the sequence number of the remark you want to delete, you can remove it by entering the no  sequence-number command.

Use the resequence access-list ipv6 command if you want to add statements to an existing access list and the sequence numbers of consecutive entries do not permit additional statements.

Task ID

Task ID

Operations

acl

read, write

Examples

In the following example, a remark is added:

RP/0/RSP0/CPU0:router(config)# ipv6 access-list Internetfilter
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 10 permit ipv6 3333:1:2:3::/64 any
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 20 permit ipv6 4444:1:2:3::/64 any
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 30 permit ipv6 5555:1:2:3::/64 any
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 39 remark Block BGP traffic from a given host
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 40 deny tcp host 6666:1:2:3::10 eq bgp host 7777:1:2:3::20 range 1300 1400
RP/0/RSP0/CPU0:router# show ipv6 access-list Internetfilter

ipv6 access-list Internetfilter
  10 permit ipv6 3333:1:2:3::/64 any
  20 permit ipv6 4444:1:2:3::/64 any
  30 permit ipv6 5555:1:2:3::/64 any
  39 remark Block BGP traffic from a given host
  40 deny tcp host 6666:1:2:3::10 eq bgp host 7777:1:2:3::20 range host 6666:1:2:3::10 eq bgp host 7777:1:2:3::20 range 1300 1400

Related Commands

Command

Description

deny (IPv6)

Sets the deny conditions for an IPv6 access list.

ipv6 access-list

Defines an IPv6 access list and enters IPv6 access list configuration mode.

permit (IPv6)

Sets permit conditions for an IPv6 access list

resequence access-list ipv6

Changes the starting entry number of the first statement in an existing IPv6 access list, and the number by which subsequent statements are incremented.

resequence access-list ipv4

To renumber existing statements and increment subsequent statements to allow a new IPv4 access list statement (permit, deny, or remark) to be added, use the resequence access-list ipv4 command in EXEC mode.

resequence access-list ipv4 name [ base [increment] ]

Syntax Description

name

Name of an IPv4 access list.

base

(Optional) Number of the first statement in the specified access list, which determines its order in the access list. Maximum value is 2147483644. Default is 10.

increment

(Optional) Number by which the base sequence number is incremented for subsequent statements. Maximum value is 2147483644. Default is 10.

Command Default

base: 10

increment: 10

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the resequence access-list ipv4 command to add a permit, deny, or remark statement between consecutive entries in an existing IPv4 access list. Specify the first entry number (the base) and the increment by which to separate the entry numbers of the statements. The software renumbers the existing statements, thereby making room to add new statements with the unused entry numbers.

Task ID

Task ID

Operations

acl

read, write

Examples

In the following example, suppose you have an existing access list:

ipv4 access-list marketing
  1 permit 10.1.1.1
  2 permit 10.2.0.0 0.0.255.255
  3 permit tcp host 10.2.2.2 255.255.0.0 any eq telnet

You want to add additional entries in the access list. First you resequence the entries, renumbering the statements starting with number 20 and an increment of 5, and then you have room for four additional statements between each of the existing statements:

RP/0/RSP0/CPU0:router# resequence access-list ipv4 marketing 20 5
RP/0/RSP0/CPU0:router# show access-lists ipv4 marketing

ipv4 access-list marketing
  20 permit 10.1.1.1
  25 permit 10.2.0.0 
  30 permit tcp host 10.2.2.2 255.255.0.0 any eq telnet

Now you add your new entries.

RP/0/RSP0/CPU0:router(config)# ipv4 access-list marketing
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 3 remark Do not allow user1 to telnet out
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 4 deny tcp host 172.16.2.88 255.255.0.0 any eq telnet
RP/0/RSP0/CPU0:router(config-ipv4-acl)# 29 remark Allow user2 to telnet out
RP/0/RSP0/CPU0:router# show access-lists ipv4 marketing

ipv4 access-list marketing
  3 remark Do not allow user1 to telnet out
  4 deny tcp host 171.69.2.88 255.255.0.0 any eq telnet
  20 permit 10.1.1.1
  25 permit 10.2.0.0
  29 remark Allow user2 to telnet out
  30 permit tcp host 10.2.2.2 255.255.0.0 any eq telnet

Related Commands

Command

Description

deny (IPv4)

Sets the deny conditions for an IPv4 access list.

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

permit (IPv4)

Sets the permit conditions for an IPv4 access list

remark (IPv4)

Inserts a helpful remark about an IPv4 access list.

show access-lists ipv4

Displays the contents of all current IPv4 access lists.

resequence access-list ipv6

To renumber existing statements and increment subsequent statements to allow a new IPv6 access list statement (permit, deny, or remark) to be added, use the resequence access-list ipv6 command in EXEC mode.

resequence access-list ipv6 name [ base [increment] ]

Syntax Description

name

Name of an IPv6 access list.

base

(Optional) Number of the first statement in the specified access list, which determines its order in the access list. Maximum value is 2147483646. Default is 10.

increment

(Optional) Number by which the base sequence number is incremented for subsequent statements. Maximum value is 2147483644. Default is 10.

Command Default

base: 10

increment: 10

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The resequence access-list ipv6 command is similar to the resequence access-list ipv4 command, except that it is IPv6 specific.

Use the resequence access-list ipv6 command to add a permit, deny, or remark statement between consecutive entries in an existing IPv6 access list. Specify the first entry number (the base) and the increment by which to separate the entry numbers of the statements. The software renumbers the existing statements, thereby making room to add new statements with the unused entry numbers.

Task ID

Task ID

Operations

acl

read, write

Examples

In the following example, suppose you have an existing access list:

ipv6 access-list Internetfilter
  10 permit ipv6 3333:1:2:3::/64 any
  20 permit ipv6 4444:1:2:3::/64 any
  30 permit ipv6 5555:1:2:3::/64 any

You want to add additional entries in the access list. First, you resequence the entries, renumbering the statements starting with number 20 and an increment of 5, and then you have room for four additional statements between each of the existing statements:

RP/0/RSP0/CPU0:router# resequence access-list ipv6 Internetfilter 20 5
RP/0/RSP0/CPU0:router# show access-lists ipv6 Internetfilter

ipv6 access-list Internetfilter
  20 permit ipv6 3333:1:2:3::/64 any
  25 permit ipv6 4444:1:2:3::/64 any
  30 permit ipv6 5555:1:2:3::/64 any

Now you add your new entries.

RP/0/RSP0/CPU0:router(config)# ipv6 access-list Internetfilter
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 3 remark Block BGP traffic from a given host
RP/0/RSP0/CPU0:router(config-ipv6-acl)# 4 deny tcp host 6666:1:2:3::10 eq bgp host 7777:1:2:3::20 range 1300 1400
RP/0/RSP0/CPU0:router# show access-lists ipv6 Internetfilter

ipv6 access-list Internetfilter
  3 remark Block BGP traffic from a given host
  4 deny tcp host 6666:1:2:3::10 eq bgp host 7777:1:2:3::20 range 1300 1404 deny tcp host 171.69.2.88 255.255.0.0 any eq telnet
  20 permit ipv6 3333:1:2:3::/64 any
  25 permit ipv6 4444:1:2:3::/64 any
  30 permit ipv6 5555:1:2:3::/64 any

Related Commands

Command

Description

deny (IPv6)

Sets the deny conditions for an IPv6 access list.

ipv6 access-list

Defines an IPv6 access list and enters IPv6 access list configuration mode.

permit (IPv6)

Set permit conditions for an IPv6 access list.

remark (IPv6)

Inserts a helpful remark about an IPv6 access list entry.

show access-lists afi-all

To display the contents of current IPv4 and IPv6 access lists, use the show access-lists afi-all command in EXEC mode.

show access-lists afi-all

Syntax Description

This command has no keywords or arguments.

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Task ID

Task ID

Operations

acl

read

Examples

The following sample output is from the show access-lists afi-all command:

RP/0/RSP0/CPU0:router# show access-lists afi-all

ipv4 access-list crypto-1
 10 permit ipv4 65.21.21.0 0.0.0.255 65.6.6.0 0.0.0.255
 20 permit ipv4 192.168.241.0 0.0.0.255 192.168.65.0 0.0.0.255

show access-lists ipv4

To display the contents of current IPv4 access lists, use the show access-lists ipv4 command in EXEC mode.

show access-lists ipv4 [ access-list-name hardware { ingress | egress } [ interface type interface-path-id ] { sequence number | location node-id } | summary [access-list-name] | access-list-name [sequence-number] | maximum [detail] [ usage pfilter { location node-id | all } ] ]

Syntax Description

access-list-name

(Optional) Name of a particular IPv4 access list. The name cannot contain spaces or quotation marks, but can include numbers.

hardware

(Optional) Identifies the access list as an access list for an interface.

ingress

(Optional) Specifies an inbound interface.

egress

(Optional) Specifies an outbound interface.

interface

(Optional) Displays interface statistics.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

interface-path-id

Physical interface or virtual interface.

Note   

Use the show interfaces command to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

sequence number

(Optional) Sequence number of a particular IPv4 access list. Range is 1 to 2147483644.

location node-id

(Optional) Location of a particular IPv4 access list. The node-id argument is entered in the rack/slot/module notation.

summary

(Optional) Displays a summary of all current IPv4 access lists.

sequence-number

(Optional) Sequence number of a particular IPv4 access list. Range is 1 to 2147483644.

maximum

(Optional) Displays the current maximum number of configurable IPv4 access control lists (ACLs) and access control entries (ACEs).

detail

(Optional) Displays complete out-of-resource (OOR) details.

usage

(Optional) Displays the usage of the access list on a given line card.

pfilter

(Optional) Displays the packet filtering usage for the specified line card.

all

(Optional) Displays the location of all the line cards.

Command Default

The default displays all IPv4 access lists.

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Use the show access-lists ipv4 command to display the contents of all IPv4 access lists. To display the contents of a specific IPv4 access list, use the name argument. Use the sequence-number argument to specify the sequence number of the access list.

Use the hardware , ingress or egress , and location keywords to display the access list hardware contents and counters for all interfaces that use the specified access list in a given direction (ingress or egress). To display the contents of a specific access list entry, use the sequence number keyword and argument. The access group for an interface must be configured using the ipv4 access-group command for access list hardware counters to be enabled.

Use the show access-lists ipv4 summary command to display a summary of all current IPv4 access lists. To display a summary of a specific IPv4 access list, use the name argument.

Use the show access-lists ipv4 maximum detail command to display the OOR details for IPv4 access lists. OOR limits the number of ACLs and ACEs that can be configured in the system. When the limit is reached, configuration of new ACLs or ACEs is rejected.

Use the show access-list ipv4 usage command to display a summary of all interfaces and access lists programmed on the specified line card.

Task ID

Task ID

Operations

acl

read

Examples

In the following example, the contents of all IPv4 access lists are displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv4

ipv4 access-list 101
  10 deny udp any any eq ntp
  20 permit tcp any any
  30 permit udp any any eq tftp
  40 permit icmp any any
  50 permit udp any any eq domain
ipv4 access-list Internetfilter
  10 permit tcp any 172.16.0.0 0.0.255.255 eq telnet
  20 deny tcp any any
  30 deny udp any 172.18.0.0 0.0.255.255 lt 1024
  40 deny ipv4 any any log

In the following example, the contents of an access list named acl_hw_1 are displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv4 acl_hw_1 hardware egress location 0/2/cp0

ipv4 access-list acl_hw_1
  10 permit icmp 192.168.36.0 0.0.0.255 any (251 hw matches)
  20 permit ip 172.16.3.0 0.0.255.255 any (29 hw matches)
  30 deny tcp any any (58 hw matches)

This table describes the significant fields shown in the display.



Table 1 show access-lists ipv4 hardware Field Descriptions

Field

Description

hw matches

Number of hardware matches.

next-hop

Next hop is programmed and is reachable through FIB.

ACL name

Name of the ACL programmed in hardware.

Sequence Number

Each ACE sequence number is programmed into hardware with all the fields that are corresponding to the values set in ACE.

Grant

Depending on the ACE rule, the grant is set to deny, permit, or both.

Logging

Logging is set to on if ACE uses a log option to enable logs.

Per ace icmp

If Per ace icmp is set to on in the hardware, ICMP is unreachable, is rate-limited, and is generated. The default is set to on.

Hits

Hardware counter for that ACE.

Statistics pointer

Statistics pointer is the pointer that is assigned for hardware counters.

Number of TCAM entries

Number of TCAM entries that are used to program the ACE into hardware.

In the following example, a summary of all IPv4 access lists are displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv4 summary

ACL Summary:
  Total ACLs configured: 3
  Total ACEs configured: 11

This table describes the significant fields shown in the display.



Table 2 show access-lists ipv4 summary Field Descriptions

Field

Description

Total ACLs configured

Number of configured IPv4 ACLs.

Total ACEs configured

Number of configured IPV4 ACEs.

In the following example, the OOR details of the IPv4 access lists are displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv4 maximum detail

Default max configurable acls :5000
Default max configurable aces :200000
Current configured acls       :1
Current configured aces       :2
Current max configurable acls :5000
Current max configurable aces :200000
Max configurable acls         :9000
Max configurable aces         :350000

This table describes the significant fields shown in the display.



Table 3 show access-lists ipv4 maximum detail Command Field Descriptions

Field

Description

Default max configurable acls

Default maximum number of configurable IPv4 ACLs allowed.

Default max configurable aces

Default maximum number of configurable IPv4 ACEs allowed.

Current configured acls

Number of configured IPv4 ACLs.

Current configured aces

Number of configured IPv4 ACEs.

Current max configurable acls

Configured maximum number of configurable IPv4 ACLs allowed.

Current max configurable aces

Configured maximum number of configurable IPv4 ACEs allowed.

Max configurable acls

Maximum number of configurable IPv4 ACLs allowed.

Max configurable aces

Maximum number of configurable IPv4 ACEs allowed.

Related Commands

Command

Description

clear access-list ipv4

Resets the IPv4 access list match counters.

copy access-list ipv4

Copies an existing IPv4 access list.

deny (IPv4)

Sets the deny conditions for an IPv4 access list.

ipv4 access-group

Filters incoming or outgoing IPv4 traffic on an interface.

ipv4 access-list

Defines an IPv4 access list and enters IPv4 access list configuration mode.

permit (IPv4)

Sets the permit conditions for an IPv4 access list

remark (IPv4)

Inserts a helpful remark about an IPv4 access list entry.

resequence access-list ipv4

Changes the starting entry number of the first statement in an existing IPv4 access list, and the number by which subsequent statements are incremented.

show access-lists ipv6

To display the contents of current IPv6 access lists, use the show access-lists ipv6 command in EXEC mode.

show access-lists ipv6 [ access-list-name hardware { ingress | egress } [ interface type interface-path-id ] { sequence number | location node-id } | summary [access-list-name] | access-list-name [sequence-number] | maximum [detail] [ usage pfilter { location node-id | all } ] ]

Syntax Description

access-list-name

(Optional) Name of a particular IPv6 access list. The name cannot contain a spaces or quotation marks, but can include numbers.

hardware

(Optional) Identifies the access list as an access list for an interface.

ingress

(Optional) Specifies an inbound interface.

egress

Specifies an outbound interface.

interface

(Optional) Displays interface statistics.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

interface-path-id

(Optional) Either a physical interface instance or a virtual interface instance as follows:

  • Physical interface instance. Naming notation is rack/slot/module/port and a slash between values is required as part of the notation.
    • rack: Chassis number of the rack.
    • slot: Physical slot number of the modular services card or line card.
    • module: Module number. A physical layer interface module (PLIM) is always 0.
    • port: Physical port number of the interface.
    Note   

    In references to a Management Ethernet interface located on a route processor card, the physical slot number is alphanumeric (RSP0) and the module is CPU0. Example: interface MgmtEth0/RSP0/CPU0/0.

  • Virtual interface instance. Number range varies depending on interface type.

For more information about the syntax for the router, use the question mark (?) online help function.

sequence number

(Optional) Sequence number of a particular IPv6 access list. Range is 1 to 2147483644.

location node-id

(Optional) Location of a particular IPv6 access list. The node-id argument is entered in the rack/slot/module notation.

summary

(Optional) Displays a summary of all current IPv6 access lists.

sequence-number

(Optional) Sequence number of a particular IPv6 access list. Range is 1 to 2147483644.

maximum

(Optional) Displays the current maximum number of configurable IPv6 access control lists (ACLs) and access control entries (ACEs).

detail

(Optional) Displays complete out-of-resource (OOR) details.

usage

(Optional) Displays the usage of the access list on a given line card.

pfilter

(Optional) Displays the packet filtering usage for the specified line card.

all

(Optional) Displays the location of all the line cards.

Command Default

Displays all IPv6 access lists.

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The show access-lists ipv6 command is similar to the show access-lists ipv4 command, except that it is IPv6 specific.

Use the show access-lists ipv6 command to display the contents of all IPv6 access lists. To display the contents of a specific IPv6 access list, use the name argument. Use the sequence-number argument to specify the sequence number of the access list.

Use thehardware , ingress or egress, and location keywords to display the access list hardware contents and counters for all interfaces that use the specified access list in a given direction (ingress or egress). To display the contents of a specific access list entry, use the sequence number keyword and argument. The access group for an interface must be configured using the ipv6 access-group command for access list hardware counters to be enabled.

Use the show access-lists ipv6 summary command to display a summary of all current IPv6 access lists. To display a summary of a specific IPv6 access list, use the name argument.

Use the show access-lists ipv6 maximum detail command to display the OOR details for IPv6 access lists. OOR limits the number of ACLs and ACEs that can be configured in the system. When the limit is reached, configuration of new ACLs or ACEs is rejected.

Use the show access-list ipv6 ipv4 usage command to display a summary of all interfaces and access lists programmed on the specified line card.

Task ID

Task ID

Operations

acl

read

Examples

In the following example, the contents of all IPv6 access lists are displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv6

ipv6 access-list Internetfilter
  3 remark Block BGP traffic from a given host
  4 deny tcp host 6666:1:2:3::10 eq bgp host 7777:1:2:3::20 range 1300 1404 deny tcp host 171.69.2.88 255.255.0.0 any eq telnet
  20 permit ipv6 3333:1:2:3::/64 any
  25 permit ipv6 4444:1:2:3::/64 any
  30 permit ipv6 5555:1:2:3::/64 any
ipv6 access-list marketing
  10 permit ipv6 7777:1:2:3::/64 any (51 matches)
  20 permit ipv6 8888:1:2:3::/64 any (26 matches)
  30 permit ipv6 9999:1:2:3::/64 any (5 matches)

In the following example, the contents of an access list named Internetfilter is displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv6 Internetfilter

ipv6 access-list Internetfilter
  3 remark Block BGP traffic from a given host
  4 deny tcp host 6666:1:2:3::10 eq bgp host 7777:1:2:3::20 range 1300 1404 deny tcp host 171.69.2.88 255.255.0.0 any eq telnet
  20 permit ipv6 3333:1:2:3::/64 any
  25 permit ipv6 4444:1:2:3::/64 any
  30 permit ipv6 5555:1:2:3::/64 any

In the following example, the contents of an access list named acl_hw_1 is displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv6 acl_hw_1 hardware egress location 0/2/cp0

ipv6 access-list acl_hw_1
  10 permit icmp any any (251 hw matches)
  20 permit ipv6 3333:1:2:3::/64 any (29 hw matches)
  30 deny tcp any any (58 hw matches)

This table describes the significant fields shown in the display.



Table 4 show access-lists ipv6 hardware Command Field Descriptions

Field

Description

hw matches

Number of hardware matches.

In the following example, a summary of all IPv6 access lists is displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv6 summary

ACL Summary:
  Total ACLs configured: 3
  Total ACEs configured: 11

This table describes the significant fields shown in the display.



Table 5 show access-lists ipv6 summary Command Field Descriptions

Field

Description

Total ACLs configured

Number of configured IPv6 ACLs.

Total ACEs configured

Number of configured IPV6 ACEs.

In the following example, the OOR details of the IPv6 access lists are displayed:

RP/0/RSP0/CPU0:router# show access-lists ipv6 maximum detail

Default max configurable acls :1000
Default max configurable aces :50000
Current configured acls       :1
Current configured aces       :2
Current max configurable acls :1000
Current max configurable aces :50000
Max configurable acls         :2000
Max configurable aces         :100000

Related Commands

Command

Description

copy access-list ipv6

Copies an existing IPv6 access list.

deny (IPv6)

Sets the deny conditions for an IPv6 access list.

ipv6 access-list

Defines an IPv6 access list and enters IPv6 access list configuration mode.

permit (IPv6)

Set permit conditions for an IPv6 access list.

remark (IPv6)

Inserts a helpful remark about an IPv6 access list entry.

resequence access-list ipv6

Changes the starting entry number of the first statement in an existing IPv4 access list, and the number by which subsequent statements are incremented.