- Index
- Preface
- Overview
- Using the Command-Line Interface
- Assigning the Switch IP Address and Default Gateway
- Configuring Cisco IOS Configuration Engine
- Clustering Switches
- Administering the Switch
- Configuring SDM Templates
- Configuring Switch-Based Authentication
- Configuring IEEE 802.1x Port-Based Authentication
- Configuring Web-Based Authentication
- Configuring Interface Characteristics
- Configuring Auto Smartports Macros
- Configuring VLANs
- Configuring VTP
- Configuring Voice VLAN
- Configuring Private VLANs
- Configuring IEEE 802.1Q and Layer 2 Protocol Tunneling
- Configuring STP
- Configuring MSTP
- Configuring Optional Spanning-Tree Features
- Configuring Flex Links and the MAC Address-Table Move Update Feature
- Configuring DHCP Features and IP Source Guard
- Configuring Dynamic ARP Inspection
- Configuring IGMP Snooping and MVR
- Configuring Port-Based Traffic Control
- Configuring CDP
- Configuring LLDP, LLDP-MED, and Wired Location Service
- Configuring UDLD
- Configuring SPAN and RSPAN
- Configuring RMON
- Configuring System Message Logging
- Configuring SNMP
- Configuring Embedded Event Manager
- Configuring Network Security with ACLs
- Configuring QoS
- Configuring EtherChannels and Link-State Tracking
- Configuring IP Unicast Routing
- Configuring IPv6 Unicast Routing
- Configuring IPv6 MLD Snooping
- Configuring IPv6 ACLs
- Configuring HSRP
- Configuring Cisco IOS IP SLAs Operations
- Configuring Enhanced Object Tracking
- Configuring Web Cache Services By Using WCCP
- Configuring IP Multicast Routing
- Configuring MSDP
- Configuring Fallback Bridging
- Troubleshooting
- Configuring Online Diagnostics
- Supported MIBs
- Working with the Cisco IOS File System, Configuration Files, and Software Images
- Unsupported Commands in Cisco IOS Release 12.2(50)SE
Configuring IPv6 ACLs
This chapter includes information about configuring IPv6 ACLs on the Catalyst 3560 switch. You can filter IP version 6 (IPv6) traffic by creating IPv6 access control lists (ACLs) and applying them to interfaces similarly to the way that you create and apply IP version 4(IPv4) named ACLs. You can also create and apply input router ACLs to filter Layer 3 management traffic.
Note To use IPv6, you must configure the dual IPv4 and IPv6 Switch Database Management (SDM) template on the switch. You select the template by entering the sdm prefer {default | dual-ipv4-and-ipv6 global configuration command.
For related information, see these chapters:
•For more information about SDM templates, see Chapter 7 "Configuring SDM Templates."
•For information about IPv6 on the switch, see Chapter 38 "Configuring IPv6 Unicast Routing."
•For information about ACLs on the switch, see Chapter 40 "Configuring IPv6 ACLs."
Note For complete syntax and usage information for the commands used in this chapter, see the command reference for this release or the Cisco IOS documentation referenced in the procedures.
This chapter contains these sections:
Understanding IPv6 ACLs
A switch image supports two types of IPv6 ACLs:
•IPv6 router ACLs
–Supported on outbound or inbound traffic on Layer 3 interfaces, which can be routed ports, switch virtual interfaces (SVIs), or Layer 3 EtherChannels.
–Applied to only IPv6 packets that are routed.
•IPv6 port ACLs
–Supported on inbound traffic on Layer 2 interfaces only.
–Applied to all IPv6 packets entering the interface.
A switch running the IP base image supports only input router IPv6 ACLs. It does not support port ACLs or output IPv6 router ACLs.
Note If you configure unsupported IPv6 ACLs, an error message appears and the configuration does not take affect.
The switch does not support VLAN ACLs (VLAN maps) for IPv6 traffic.
Note For more information about ACL support on the switch, see Chapter 34 "Configuring Network Security with ACLs."
You can apply both IPv4 and IPv6 ACLs to an interface.
As with IPv4 ACLs, IPv6 port ACLs take precedence over router ACLs:
•When an input router ACL and input port ACL exist in an SVI, packets received on ports to which a port ACL is applied are filtered by the port ACL. Routed IP packets received on other ports are filtered by the router ACL. Other packets are not filtered.
•When an output router ACL and input port ACL exist in an SVI, packets received on the ports to which a port ACL is applied are filtered by the port ACL. Outgoing routed IPv6 packets are filtered by the router ACL. Other packets are not filtered.
Note If any port ACL (IPv4, IPv6, or MAC) is applied to an interface, that port ACL is used to filter packets, and any router ACLs attached to the SVI of the port VLAN are ignored.
These sections describe some characteristics of IPv6 ACLs on the switch:
Supported ACL Features
IPv6 ACLs on the switch have these characteristics:
•Fragmented frames (the fragments keyword as in IPv4) are supported.
•The same statistics supported in IPv4 are supported for IPv6 ACLs.
•If the switch runs out of TCAM space, packets associated with the ACL label are forwarded to the CPU, and the ACLs are applied in software.
•Routed or bridged packets with hop-by-hop options have IPv6 ACLs applied in software.
•Logging is supported for router ACLs, but not for port ACLs.
IPv6 ACL Limitations
With IPv4, you can configure standard and extended numbered IP ACLs, named IP ACLs, and MAC ACLs. IPv6 supports only named ACLs.
The switch supports most Cisco IOS-supported IPv6 ACLs with some exceptions:
•IPv6 source and destination addresses—ACL matching is supported only on prefixes from /0 to /64 and host addresses (/128) that are in the extended universal identifier (EUI)-64 format. The switch supports only these host addresses with no loss of information:
–aggregatable global unicast addresses
–link local addresses
•The switch does not support matching on these keywords: flowlabel, routing header, and undetermined-transport.
•The switch does not support reflexive ACLs (the reflect keyword).
•This release supports only port ACLs and router ACLs for IPv6; it does not support VLAN ACLs (VLAN maps).
•The switch does not apply MAC-based ACLs on IPv6 frames.
•You cannot apply IPv6 port ACLs to Layer 2 EtherChannels.
•The switch does not support output port ACLs.
•Output router ACLs and input port ACLs for IPv6 are supported only on switches. Switches support only control plane (incoming) IPv6 ACLs.
•When configuring an ACL, there is no restriction on keywords entered in the ACL, regardless of whether or not they are supported on the platform. When you apply the ACL to an interface that requires hardware forwarding (physical ports or SVIs), the switch checks to determine whether or not the ACL can be supported on the interface. If not, attaching the ACL is rejected.
•If an ACL is applied to an interface and you attempt to add an access control entry (ACE) with an unsupported keyword, the switch does not allow the ACE to be added to the ACL that is currently attached to the interface.
Configuring IPv6 ACLs
Before configuring IPv6 ACLs, you must select one of the dual IPv4 and IPv6 SDM templates.
To filter IPv6 traffic, you perform these steps:
Step 1 Create an IPv6 ACL, and enter IPv6 access list configuration mode.
Step 2 Configure the IPv6 ACL to block (deny) or pass (permit) traffic.
Step 3 Apply the IPv6 ACL to an interface. For router ACLs, you must also configure an IPv6 address on the Layer 3 interface to which the ACL is applied.
These sections describe how to configure and apply IPv6 ACLs:
•Default IPv6 ACL Configuration
•Interaction with Other Features
•Applying an IPv6 ACL to an Interface
Default IPv6 ACL Configuration
There are no IPv6 ACLs configured or applied.
Interaction with Other Features
Configuring IPv6 ACLs has these interactions with other features or switch characteristics:
•If an IPv6 router ACL is configured to deny a packet, the packet is dropped. A copy of the packet is sent to the Internet Control Message Protocol (ICMP) queue to generate an ICMP unreachable message for the frame.
•If a bridged frame is to be dropped due to a port ACL, the frame is not bridged.
•You can create both IPv4 and IPv6 ACLs on a switch, and you can apply both IPv4 and IPv6 ACLs to the same interface. Each ACL must have a unique name; an error message appears if you try to use a name that is already configured.
You use different commands to create IPv4 and IPv6 ACLs and to attach IPv4 or IPv6 ACLs to the same Layer 2 or Layer 3 interface. If you use the wrong command to attach an ACL (for example, an IPv4 command to attach an IPv6 ACL), you receive an error message.
•You cannot use MAC ACLs to filter IPv6 frames. MAC ACLs can only filter non-IP frames.
•If the TCAM is full, for any additional configured ACLs, packets are forwarded to the CPU, and the ACLs are applied in software.
Creating IPv6 ACLs
Beginning in privileged EXEC mode, follow these steps to create an IPv6 ACL:
Use the no deny | permit IPv6 access-list configuration commands with keywords to remove the deny or permit conditions from the specified access list.
This example configures the IPv6 access list named CISCO. The first deny entry in the list denies all packets that have a destination TCP port number greater than 5000. The second deny entry denies packets that have a source UDP port number less than 5000. The second deny also logs all matches to the console. The first permit entry in the list permits all ICMP packets. The second permit entry in the list permits all other traffic. The second permit entry is necessary because an implicit deny -all condition is at the end of each IPv6 access list.
Switch(config)# ipv6 access-list CISCO
Switch(config-ipv6-acl)# deny tcp any any gt 5000
Switch config-ipv6-acl)# deny ::/0 lt 5000 ::/0 log
Switch(config-ipv6-acl)# permit icmp any any
Switch(config-ipv6-acl)# permit any any
Applying an IPv6 ACL to an Interface
This section describes how to apply IPv6 ACLs to network interfaces. You can apply an ACL to outbound or inbound traffic on Layer 3 interfaces, or to inbound traffic on Layer 2 interfaces.
Beginning in privileged EXEC mode, follow these steps to control access to an interface:
Use the no ipv6 traffic-filter access-list-name interface configuration command to remove an access list from an interface.
This example shows how to apply the access list Cisco to outbound traffic on a Layer 3 interface:
Switch(config)# interface gigabitethernet0/3
Switch(config-if)# no switchport
Switch(config-if)# ipv6 address 2001::/64 eui-64
Switch(config-if)# ipv6 traffic-filter CISCO out
Displaying IPv6 ACLs
You can display information about all configured access lists, all IPv6 access lists, or a specific access list by using one or more of the privileged EXEC commands in Table 40-1.
This is an example of the output from the show access-lists privileged EXEC command. The output shows all access lists that are configured on the switch.
Switch #show access-lists
Extended IP access list hello
10 permit ip any any
IPv6 access list ipv6
permit ipv6 any any sequence 10
This is an example of the output from the show ipv6 access-lists privileged EXEC command. The output shows only IPv6 access lists configured on the switch.
Switch# show ipv6 access-list
IPv6 access list inbound
permit tcp any any eq bgp (8 matches) sequence 10
permit tcp any any eq telnet (15 matches) sequence 20
permit udp any any sequence 30
IPv6 access list outbound
deny udp any any sequence 10
deny tcp any any eq telnet sequence 20