Guest

Support

Interface Commands (show ip interface -- tx-queue-limit)

Table Of Contents

show ip interface

show pas eswitch address

show rif

show service-module serial

show smf

shutdown (controller)

shutdown (hub)

shutdown (interface)

smt-queue-threshold

snmp trap illegal-address

source-address

speed

squelch

t1 bert

t1 clock source

t1 external

t1 fdl ansi

t1 framing

t1 linecode

t1 test

t1 timeslot

t1 yellow

test interface fastethernet

test service-module

timeslot

transmit-buffers backing-store

transmit-clock-internal

transmitter-delay

ts16

tunnel checksum

tunnel destination

tunnel key

tunnel mode

tunnel sequence-datagrams

tunnel source

tx-queue-limit


show ip interface

To display the usability status of interfaces configured for IP, use the show ip interface command in privileged EXEC mode.

show ip interface [type number] [brief]

Syntax Description

type

(Optional) Interface type.

number

(Optional) Interface number.

brief

(Optional) Displays a summary of the usability status information for each interface.


Command Modes

Privileged EXEC

Command History

Release
Modification

10.0

This command was introduced.

12.0(3)T

This command was expanded to include the status of ip wccp redirect out and ip wccp redirect exclude add in commands.

12.2(14)S

This command was expanded to display the status of NetFlow on a subinterface.

12.2(15)T

The command output enhancements introduced in Cisco IOS Release 12.2(14)S were integrated into Cisco IOS Release 12.2(15)T.

12.3(6)

The command output was modified to identify the downstream VRF in the output.

12.3(11)T

This command was integrated into Cisco IOS Release 12.3(11)T.

12.3(14)YM2

This command was modified to show the usability status of interfaces configured for Multi-Processor Forwarding (MPF) and implemented on the Cisco 7301 and Cisco 7206VXR routers.

12.4(4)T

This command was integrated into Cisco IOS Release 12.4(4)T.

12.2(28)SB

This command was integrated into Cisco IOS Release 12.2(28)SB.


Usage Guidelines

The Cisco IOS software automatically enters a directly connected route in the routing table if the interface is usable. A usable interface can send and receive packets. If an interface is not usable, the directly connected routing entry is removed from the routing table. Removing the entry allows the software to use dynamic routing protocols to determine backup routes to the network, if any.

If the interface can provide two-way communication, the line protocol is marked "up." If the interface hardware is usable, the interface is marked "up."

If you specify an optional interface type, you see information for that specific interface.

If you specify no optional arguments, you see information on all the interfaces.

When an asynchronous interface is encapsulated with PPP or Serial Line Internet Protocol (SLIP), IP fast switching is enabled. A show ip interface command on an asynchronous interface encapsulated with PPP or SLIP displays a message indicating that IP fast switching is enabled.

The show ip interface brief command can be used to view a summary of the router interfaces. This command displays the IP address, interface status, and additional information.

Examples

The following examples from Cisco IOS Release 12.3(14)YM2 show:

Configuration information on interface Gigabit Ethernet0/3, where the IP flow egress feature is configured on the output side (where packets go out of the interface) and the policy route-map named PBR_NAME is configured on the input side (where packets come into the interface).

Interface information on Gigabit Ethernet interface 0/3 showing that MPF is enabled and that both features are not supported by MPF and are ignored.

The highlighted arrows (for documentation purposes only) show the configured output and input features and the additional MPF interface information.

Router# show running-config interface g 0/3

interface GigabitEthernet0/3
 ip address 10.1.1.1 255.255.0.0
 ip flow egress                   <== output
 ip policy route-map PBR_NAME     <== input
 duplex auto
 speed auto
 media-type gbic
 negotiation auto
end

Router# show ip interface g 0/3

GigabitEthernet0/3 is up, line protocol is up
  Internet address is 10.1.1.1/16
  Broadcast address is 255.255.255.255
  Address determined by setup command
  MTU is 1500 bytes
  Helper address is not set
  Directed broadcast forwarding is disabled
  Outgoing access list is not set
  Inbound access list is not set
  Proxy ARP is enabled
  Local Proxy ARP is disabled
  Security level is default
  Split horizon is enabled
  ICMP redirects are always sent
  ICMP unreachables are always sent
  ICMP mask replies are never sent
  IP fast switching is enabled
  IP fast switching on the same interface is disabled
  IP Flow switching is disabled
  IP CEF switching is enabled
  IP Feature Fast switching turbo vector
  IP VPN Flow CEF switching turbo vector
  IP multicast fast switching is enabled
  IP multicast distributed fast switching is disabled
  IP route-cache flags are Fast, CEF
  Router Discovery is disabled
  IP output packet accounting is disabled
  IP access violation accounting is disabled
  TCP/IP header compression is disabled
  RTP/IP header compression is disabled
  Policy routing is enabled, using route map PBR
  Network address translation is disabled
  BGP Policy Mapping is disabled
  IP Multi-Processor Forwarding is enabled   <======== MPF information
     IP Input features, "PBR",
         are not supported by MPF and are IGNORED
     IP Output features, "NetFlow",
         are not supported by MPF and are IGNORED

The following example identifies a downstream VRF. The highlighted line (for documentation purposes only) identifies the downstream VRF.

Router# show ip interface vi 3

Virtual-Access3 is up, line protocol is up
  Interface is unnumbered. Using address of Loopback2 (10.0.0.8)
  Broadcast address is 255.255.255.255
  Peer address is 10.8.1.1
  MTU is 1492 bytes
  Helper address is not set
  Directed broadcast forwarding is disabled
  Outgoing access list is not set
  Inbound  access list is not set
  Proxy ARP is enabled
  Local Proxy ARP is disabled
  Security level is default
  Split horizon is enabled
  ICMP redirects are always sent
  ICMP unreachables are always sent
  ICMP mask replies are never sent
  IP fast switching is enabled
  IP fast switching on the same interface is enabled
  IP Flow switching is disabled
  IP CEF switching is enabled
  IP Feature Fast switching turbo vector
  IP VPN CEF switching turbo vector
  VPN Routing/Forwarding "U"
  Downstream VPN Routing/Forwarding "D" 
  IP multicast fast switching is disabled
  IP multicast distributed fast switching is disabled
  IP route-cache flags are Fast, CEF
  Router Discovery is disabled
  IP output packet accounting is disabled
  IP access violation accounting is disabled
  TCP/IP header compression is disabled
  RTP/IP header compression is disabled
  Policy routing is disabled
  Network address translation is disabled
  WCCP Redirect outbound is disabled
  WCCP Redirect inbound is disabled
  WCCP Redirect exclude is disabled
  BGP Policy Mapping is disabled 

Table 53 describes the significant fields shown in the display.

Table 53 show ip interface Field Descriptions 

Field
Description

Virtual-Access3 is up

If the interface hardware is usable, the interface is marked "up." For an interface to be usable, both the interface hardware and line protocol must be up.

Broadcast address is

Displays the broadcast address.

Peer address is

Displays the peer address.

MTU is

Displays the MTU value set on the interface.

Helper address

Displays a helper address, if one has been set.

Directed broadcast forwarding

Indicates whether directed broadcast forwarding is enabled.

Outgoing access list

Indicates whether the interface has an outgoing access list set.

Inbound access list

Indicates whether the interface has an incoming access list set.

Proxy ARP

Indicates whether Proxy Address Resolution Protocol (ARP) is enabled for the interface.

Security level

Specifies the IP Security Option (IPSO) security level set for this interface.

Split horizon

Indicates that split horizon is enabled.

ICMP redirects

Specifies whether redirect messages will be sent on this interface.

ICMP unreachables

Specifies whether unreachable messages will be sent on this interface.

ICMP mask replies

Specifies whether mask replies will be sent on this interface.

IP fast switching

Specifies whether fast switching has been enabled for this interface. It is generally enabled on serial interfaces, such as this one.

IP Flow switching

Specifies whether Flow switching is enabled for this interface.

IP CEF switching

Specifies whether Cisco Express Forwarding is enabled for the interface.

Downstream VPN Routing/Forwarding "D"

Specifies the VRF where the PPP peer routes and AAA per-user routes are being installed.

IP multicast fast switching

Specifies whether multicast fast switching is enabled for the interface.

IP route-cache flags are Fast, Flow init, CEF, Ingress Flow

Specifies whether NetFlow has been enabled on an interface. Displays "Flow init" to specify that NetFlow is enabled on the interface. Displays "Ingress Flow" to specify that NetFlow is enabled on a subinterface using the ip flow ingress command. Specifies "Flow" to specify that NetFlow is enabled on a main interface using the ip route-cache flow command.

Router Discovery

Specifies whether the discovery process has been enabled for this interface. It is generally disabled on serial interfaces.

IP output packet accounting

Specifies whether IP accounting is enabled for this interface and what the threshold (maximum number of entries) is.

TCP/IP header compression

Indicates whether compression is enabled or disabled.

WCCP Redirect outbound is disabled

Indicates the status of whether packets received on an interface are redirected to a cache engine. Displays "enabled" or "disabled."

WCCP Redirect exclude is disabled

Indicates the status of whether packets targeted for an interface will be excluded from being redirected to a cache engine. Displays "enabled" or "disabled."


The following is sample output from the show ip interface brief command:

Router# show ip interface brief

Interface     IP-Address     OK?  Method  Status                  Protocol
Ethernet0     10.108.00.5    YES  NVRAM   up                      up      
Ethernet1     unassigned     YES  unset   administratively down   down    
Loopback0     10.108.200.5   YES  NVRAM   up                      up      
Serial0       10.108.100.5   YES  NVRAM   up                      up      
Serial1       10.108.40.5    YES  NVRAM   up                      up      
Serial2       10.108.100.5   YES  manual  up                      up      
Serial3       unassigned     YES  unset   administratively down   down 

Table 54 show ip interface brief Field Descriptions 

Field
Description

Interface

Type of interface.

IP-Address

IP Address assigned to the interface.

OK?

"Yes" means that the IP Address is currently valid. "No" means that the IP Address is not currently valid.

Method

The method field has the following possible values:

RARP or SLARP—Reverse Address Resolution Protocol (RARP) or Serial Line Address Resolution Protocol (SLARP) request

BOOTP—Bootstrap protocol

TFTP—Configuration file obtained from TFTP server

manual—Manually changed by CLI command

NVRAM—Configuration file in NVRAM

IPCP—ip address negotiated command

DHCP—ip address dhcp command

unassigned—No IP address

unset—Unset

other—Unknown

Status

Indicates the status of interface. Valid values and their meanings are:

up—Interface is administratively up.

down—Interface is administratively down.

administratively down—Interface is administratively down.

Protocol

Indicates the operational status of the routing protocol on this interface.


Related Commands

Command
Description

ip address

Sets a primary or secondary IP address for an interface.

ip vrf autoclassify

Enables VRF autoclassify on a source interface.

match ip source

Specifies a source IP address to match to required route maps that have been set up based on VRF connected routes.

route-map

Defines the conditions for redistributing routes from one routing protocol into another, or to enable policy routing.

set vrf

Enables VPN VRF selection within a route map for policy-based routing VRF selection.

show ip arp

Displays the ARP cache, in which SLIP addresses appear as permanent ARP table entries.

show route-map

Displays static and dynamic route maps.


show pas eswitch address

To display the Layer 2 learned addresses for an interface, use the show pas eswitch address EXEC command.

show pas eswitch address [ethernet | fastethernet] [slot/port]

Syntax Description

ethernet | fastethernet

(Optional) Specify the type of interface.

slot

(Optional) Slot number of the interface.

port

(Optional) Interface number.


Command Modes

EXEC

Command History

Release
Modification

11.2 P

This command was introduced.


Examples

The following sample output shows that the first PA-12E/2FE interface (listed below as port 0) in port adapter slot 3 has learned the Layer 2 address 00e0.f7a4.5100 for bridge group 30 (listed below as BG 30):

Router# show pas eswitch address fastethernet 3/0

U 00e0.f7a4.5100, AgeTs 56273 s, BG 30 (vLAN 0), Port 0

show rif

To display the current contents of the RIF cache, use the show rif EXEC command.

show rif

Syntax Description

This command has no arguments or keywords.

Command Modes

EXEC

Command History

Release
Modification

10.0

This command was introduced.


Examples

The following is sample output from the show rif command:

Router# show rif

Codes: * interface, - static, + remote
Hardware Addr  How   Idle (min)  Routing Information Field
5C02.0001.4322 rg5           -   0630.0053.00B0
5A00.0000.2333 TR0           3   08B0.0101.2201.0FF0
5B01.0000.4444 -             -   -
0000.1403.4800 TR1           0   -
0000.2805.4C00 TR0           *   -
0000.2807.4C00 TR1           *   -
0000.28A8.4800 TR0           0   -
0077.2201.0001 rg5          10   0830.0052.2201.0FF0

In the display, entries marked with an asterisk (*) are the router/bridge's interface addresses. Entries marked with a dash (-) are static entries. Entries with a number are cached entries. If the RIF timeout is set to something other than the default of 15 minutes, the timeout is displayed at the top of the display.

Table 55 describes significant fields shown in the display.

Table 55 Show RIF Cache Display Field Descriptions

Field
Description

Hardware Addr

Lists the MAC-level addresses.

How

Describes how the RIF has been learned. Possible values include a ring group (rg), or interface (TR).

Idle (min)

Indicates how long, in minutes, since the last response was received directly from this node.

Routing Information Field

Lists the RIF.


show service-module serial

To display the performance report for an integrated CSU/DSU, use the show service-module serial privileged EXEC command.

show service-module serial number [performance-statistics [interval-range]]

Syntax Description

number

Interface number 0 or 1.

performance-statistics

(Optional) Displays the CSU/DSU performance statistics for the past 24 hours. This keyword applies only to the fractional T1/T1 module.

interval-range

(Optional) Specifies the number of 15-minute intervals displayed. You can choose a range from 1 to 96, where each value represents the CSU/DSU activity performed in that 15-minute interval. For example, a range of 2-3 displays the performance statistics for the intervals two and three.


Command Modes

Privileged EXEC

Command History

Release
Modification

11.2

This command was introduced.


Usage Guidelines

This command applies to the 2- and 4-wire 56/64-kbps CSU/DSU module and FT1/T1 CSU/DSU module. The performance-statistics keyword applies only to the FT1/T1 CSU/DSU module.

Examples

The following sample output shows CSU/DSU performance statistics on a Cisco 2524 or Cisco 2525 router for intervals 30 to 32. Each interval is 15 minutes long. All the data is zero because no errors were discovered on the T1 line:

Router# show service-module serial 1 performance-statistics 30-32

Total Data (last 58 15 minute intervals):
    0 Line Code Violations, 0 Path Code Violations
    0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
Data in current interval (131 seconds elapsed):
    0 Line Code Violations, 0 Path Code Violations
    0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
Data in Interval 30:
    0 Line Code Violations, 0 Path Code Violations
    0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
Data in Interval 31:
    0 Line Code Violations, 0 Path Code Violations
    0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
Data in Interval 32:
    0 Line Code Violations, 0 Path Code Violations
    0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs

The following example is sample output from the show service-module serial command:

Router1# show service-module serial 0

Module type is T1/fractional
    Hardware revision is B, Software revision is 1.1 ,
    Image checksum is 0x2160B7C, Protocol revision is 1.1
Receiver has AIS alarm,
Unit is currently in test mode:
    line loopback is in progress
Framing is ESF, Line Code is B8ZS, Current clock source is line,
Fraction has 24 timeslots (64 Kbits/sec each), Net bandwidth is 1536 Kbits/sec.
Last user loopback performed:
    remote loopback
    Failed to loopup remote
Last module self-test (done at startup): Passed
Last clearing of alarm counters 0:05:50
    loss of signal        :    1, last occurred 0:01:50
    loss of frame         :    0,
    AIS alarm             :    1, current duration 0:00:49
    Remote alarm          :    0,
    Module access errors  :    0,
Total Data (last 0 15 minute intervals):
Line Code Violations, 0 Path Code Violations
    0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
Data in current interval (351 seconds elapsed):
    1466 Line Code Violations, 0 Path Code Violations
    25 Slip Secs, 49 Fr Loss Secs, 40 Line Err Secs, 1 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 49 Unavail Secs

Router1# show service-module serial 1

Module type is 4-wire Switched 56
    Hardware revision is B, Software revision is 1.00,
    Image checksum is 0x44453634, Protocol revision is 1.0
Connection state: active,
Receiver has loss of signal, loss of sealing current,
Unit is currently in test mode:
    line loopback is in progress
Current line rate is 56 Kbits/sec
Last user loopback performed:
    dte loopback
    duration 00:00:58
Last module self-test (done at startup): Passed
Last clearing of alarm counters 0:13:54
    oos/oof               :    3, last occurred 0:00:24
    loss of signal        :    3, current duration 0:00:24
    loss of sealing curren:    2, current duration 0:04:39
    loss of frame         :    0,
    rate adaption attempts:    0,

The following example shows sample output from the show service-module serial command issued on a Cisco 3640 modular access router:

router# show service-module serial 0/1

Module type is 4-wire Switched 56
    Hardware revision is B, Software revision is 1.00,
    Image checksum is 0x42364436, Protocol revision is 1.0
Connection state: Idle
Receiver has no alarms.
CSU/DSU Alarm mask is 0
Current line rate is 56 Kbits/sec
Last module self-test (done at startup): Passed
Last clearing of alarm counters 4d02h
    oos/oof               :    0,
    loss of signal        :    0,
    loss of sealing curren:    0,
    loss of frame         :    0,
    rate adaptation attemp:    0,

The following example shows sample output from the show service-module serial command issued on a Cisco 1605 router:

router# show service-module serial 0

Module type is 4-wire Switched 56
    Hardware revision is B, Software revision is 1.00,
    Image checksum is 0x42364436, Protocol revision is 1.0
Receiver has oos/oof, loss of signal,
CSU/DSU Alarm mask is 4
Current line rate is 56 Kbits/sec
Last module self-test (done at startup): Passed
Last clearing of alarm counters 1d02h
    oos/oof               :    1, current duration 1d02h
    loss of signal        :    1, current duration 1d02h
    loss of frame         :    0,
    rate adaptation attemp:    0,

Table 56 describes the fields displayed by the show service-module serial command.

     

Table 56 show service-module Output Field Descriptions 

Field
Description

Module type

The CSU/DSU module installed in the router. The possible modules are T1/fractional, 2-wire switched 56-kbps, and 4-wire 56/64-kbps.

Receiver has AIS alarm

Alarms detected by the FT1/T1 CSU/DSU module or 2- and 4-wire 56/64-kbps CSU/DSU modules.

Possible T1 alarms are as follows:

Transmitter is sending remote alarm.

Transmitter is sending AIS.

Receiver has loss of signal.

Receiver has loss of frame.

Receiver has remote alarm.

Receiver has no alarms.

Possible switched 56k alarms are as follows:

Receiver has loss of signal

Receiver has loss of sealing current

Receiver has loss of frame

Receiver has rate adaptation attempts

Unit is currently in test mode

Loopback tests are in progress.

Framing is ESF

Indicates frame type used on the line. Can be extended super frame or super frame.

Line Code is B8ZS

Indicated line-code type configured. Can be alternate mark inversion (AMI) or binary 8-zero substitution (B8ZS).

Current clock source is line

Clock source configured on the line, which can be supplied by the service provider (line) or the integrated CSU/DSU module (internal).

Fraction has 24 timeslots

Number of timeslots defined for the FT1/T1 module, which can range from 1 to 24.

Net bandwidth

Total bandwidth of the line (for example, 24 timeslots multiplied by 64 kbps equals a bandwidth of 1536 kbps).

Last user loopback performed

Type and outcome of the last performed loopback.

Last module self-test (done at startup): Passed

Status of the last self test performed on an integrated CSU/DSU module.

Last clearing of alarm counters

List of network alarms that were detected and cleared on the CSU/DSU module.

Total Data
Data in current interval

Shows the current accumulation period, which rolls into the 24-hour accumulation every 15 minutes. The oldest 15-minute period falls off the back of the 24-hour accumulation buffer.

Line Code Violations

Indicates the occurrence of either a bipolar violation or excessive zeroes error event.

Path Code Violations

Indicates a frame synchronization bit error in the D4 and E1-no CRC formats or a CRC error in the ESF and E1-CRC formats.

Slip Secs

Indicates the replication or detection of the payload bits of a DS1 frame. A slip may be performed when there is a difference between the timing of a synchronous receiving terminal and the received signal.

Fr Loss Secs

Indicates the number of seconds an out of frame error is detected.

Line Err Secs

Line errored seconds is a second in which one or more line code violation errors are detected.

Errored Secs

In ESF and E1-CRC links, an errored second is a second in which one of the following is detected: one or more path code violations; one or more out of frame defects; one or more controlled slip events; a detected AIS defect.

For D4 and E1-no CRC links, the presence of bipolar violation also triggers an errored second.

Bursty Err Secs

A second with fewer than 320 and more than 1 path coding violation errors. No severely errored frame defects or incoming AIS defects are detected. Controlled slips are not included in this parameter.

Severely Err Secs

For ESF signals, a second with one of the following errors: 320 or more path code violation errors; one or more out of frame defects; a detected AIS defect.

For D4 signals, a count of 1-second intervals with framing errors, or an out of frame defect, or 1544 line code violations.

Unavail Secs

Total time the line was out of service.


Related Commands

Command
Description

clear service-module serial

Resets an integrated CSU/DSU.


show smf

To display the configured software MAC address filter (SMF) on various interfaces of a router, use the show smf EXEC command.

show smf [interface-name]

Syntax Description

interface-name

Displays information about the specified interface. Choices can include atm, ethernet, fastethernet, null, serial, tokenring, and async.


Command Modes

EXEC

Command History

Release
Modification

10.0

This command was introduced in a release prior to 10.0.


Usage Guidelines

The SMF is active whenever the router is doing bridging or IRB. MAC address filtering can be used as a security feature in bridging or switching environments.

Examples

The following is sample output from the show smf command:

R2-81-7206#sh smf

 Software MAC address filter on FastEthernet0/0.2
  Hash Len    Address      Matches  Act      Type
  0x00:  0 ffff.ffff.ffff         0 RCV Physical broadcast
  0x0C:  0 0100.0c00.0000         0 RCV ISL vLAN Multicast
  0x2A:  0 0900.2b01.0001         0 RCV DEC spanning tree
  0xA6:  0 0010.a6ae.6000         0 RCV Interface MAC address
  0xC1:  0 0100.0ccc.cccd         0 RCV SSTP MAC address
  0xC2:  0 0180.c200.0000         0 RCV IEEE spanning tree
  0xC2:  1 0180.c200.0000         0 RCV IBM spanning tree
  0xC2:  2 0100.0ccd.cdce         0 RCV VLAN Bridge STP
N

Table 57 describes the fields shown in this display.

Table 57 show smf Field Descriptions 

Field
Description

Hash

Position in the hash table for this entry.

Len

Length of the entry.

Address

MAC address for the interface.

Matches

Number of hits for the address

Act

Action taken. Values can be receive (RCV), forward (FWD), or discard (DIS).

Type

Type of MAC address.


shutdown (controller)

To disable the Channelized T3 Interface Processor (CT3IP) in Cisco 7500 series routers, use the shutdown (controller) configuration command. To restart a disabled CT3IP, use the no form of this command.

shutdown

no shutdown

Syntax Description

This command has no arguments or keywords.

Defaults

Enabled

Command Modes

Controller configuration

Command History

Release
Modification

11.3

This command was introduced.


Usage Guidelines

Shutting down the CT3IP disables all functions on the interface and sends a blue alarm to the network. This command marks the interface as unavailable. To check if the CT3IP is disabled, use the show controller t3 command.

Examples

The following example shuts down the CT3IP:

controller t3 9/0/0
 shutdown

Related Commands

Command
Description

show controllers t3

Displays information about the CT3IP on Cisco 7500 series routers.


shutdown (hub)

Use the shutdown (hub) configuration command to shut down a port on an Ethernet hub of a Cisco 2505 or Cisco 2507. Use the no form of this command to restart the disabled hub.

shutdown

no shutdown

Syntax Description

This command has no arguments or keywords.

Command Modes

Hub configuration

Command History

Release
Modification

10.3

This command was introduced.


Examples

The following example shuts down hub 0, ports 1 through 3:

hub ethernet 0 1 3
 shutdown

Related Commands

Command
Description

hub

Enables and configures a port on an Ethernet hub of a Cisco 2505 or Cisco 2507.


shutdown (interface)

To disable an interface, use the shutdown configuration command. To restart a disabled interface, use the no form of this command.

shutdown

no shutdown

Syntax Description

This command has no arguments or keywords.

Defaults

Enabled

Command Modes

Interface configuration

Command History

Release
Modification

10.0

This command was introduced.


Usage Guidelines

The shutdown command disables all functions on the specified interface. On serial interfaces, this command causes the DTR signal to be dropped. On Token Ring interfaces, this command causes the interface to be deinserted from the ring. On FDDI interfaces, this command causes the optical bypass switch, if present, to go into bypass mode.

This command also marks the interface as unavailable. To check whether an interface is disabled, use the EXEC command show interfaces. An interface that has been shut down is shown as administratively down in the display from this command.

Examples

The following example turns off Ethernet interface 0:

interface ethernet 0 
 shutdown

The following example turns the interface back on:

interface ethernet 0 
 no shutdown

Related Commands

Command
Description

interface

Configures an interface type and enters interface configuration mode.

show interfaces

Displays statistics for all interfaces configured on the router or access server.


smt-queue-threshold

To set the maximum number of unprocessed FDDI station management (SMT) frames that will be held for processing, use the smt-queue-threshold global configuration command. Use the no form of this command to restore the queue to the default.

smt-queue-threshold number

no smt-queue-threshold

Syntax Description

number

Number of buffers used to store unprocessed SMT messages that are to be queued for processing. Acceptable values are positive integers.


Defaults

The default threshold value is equal to the number of FDDI interfaces installed in the router.

Command Modes

Global configuration

Command History

Release
Modification

10.0

This command was introduced.


Usage Guidelines

This command helps ensure that the routers keep track of FDDI upstream and downstream neighbors, particularly when a router includes more than one FDDI interface.

In FDDI, upstream and downstream neighbors are determined by transmitting and receiving SMT Neighbor Information Frames (NIFs). The router can appear to lose track of neighbors when it receives an SMT frame and the queue currently contains an unprocessed frame. This occurs because the router discards incoming SMT frames if the queue is full. Discarding SMT NIF frames can cause the router to lose its upstream or downstream neighbor.


Note Use this command carefully because the SMT buffer is charged to the inbound interface (input hold queue) until the frame is completely processed by the system. Setting this value to a high limit can impact buffer usage and the ability of the router to receive routable packets or routing updates.


Examples

The following example specifies that the SMT queue can hold ten messages. As SMT frames are processed by the system, the queue is decreased by one:

smt-queue-threshold 10

snmp trap illegal-address

To issue an SNMP trap when a MAC address violation is detected on an Ethernet hub port of a Cisco 2505, Cisco 2507, or Cisco 2516 router, use the snmp trap illegal-address hub configuration command. Use the no form to disable this function.

snmp trap illegal-address

no snmp trap illegal-address

Syntax Description

This command has no arguments or keywords.

Defaults

No SNMP trap is issued.

Command Modes

Hub configuration

Command History

Release
Modification

11.1

This command was introduced.


Usage Guidelines

In addition to setting the snmp trap illegal-address command on the Ethernet hub, you can set the frequency that the trap is sent to the network management station (NMS). This is done on the NMS via the Cisco Repeater MIB. The frequency of the trap can be configured for once only or at a decaying rate (the default). If the decaying rate is used, the first trap is sent immediately, the second trap is sent after one minute, the third trap is sent after two minutes, and so on until 32 minutes at which time the trap is sent every 32 minutes. If you use a decaying rate, you can also set the trap acknowledgment so the trap will be acknowledged after it is received and will no longer be sent to the network management station.

Because traps are not reliable, additional information on a port basis is provided by the Cisco Repeater MIB. The network management function can query the following information: the last illegal MAC source address, the illegal address trap acknowledgment, the illegal address trap enabled, the illegal address first heard (timestamp), the illegal address last heard (timestamp), the last illegal address trap count for the port, and the illegal address trap total count for the port.

In addition to issuing a trap when a MAC address violation is detected, the port is also disabled as long as the MAC address is invalid. The port is enabled and the trap is no longer sent when the MAC address is valid (that is, either the address was configured correctly or learned).

Examples

The following example enables an SNMP trap to be issued when a MAC address violation is detected on hub ports 2, 3, or 4. SNMP support must already be configured on the router.

hub ethernet 0 2 4
snmp trap illegal-address

Related Commands

Command
Description

hub

Enables and configures a port on an Ethernet hub of a Cisco 2505 or Cisco 2507.


source-address

To configure source address control on a port on an Ethernet hub of a Cisco 2505 or Cisco 2507, use the source-address hub configuration command. To remove a previously defined source address, use the no form of this command.

source-address [mac-address]

no source-address

Syntax Description

mac-address

(Optional) MAC address in the packets that the hub will allow to access the network.


Defaults

Disabled

Command Modes

Hub configuration

Command History

Release
Modification

10.3

This command was introduced.


Usage Guidelines

If you omit the MAC address, the hub uses the value in the last source address register, and if the address register is invalid, it will remember the first MAC address it receives on the previously specified port, and allow only packets from that MAC address onto that port.

Examples

The following example configures the hub to allow only packets from MAC address 1111.2222.3333 on port 2 of hub 0:

hub ethernet 0 2
source-address 1111.2222.3333

The following example configures the hub to use the value of the last source address register. If the address register is invalid, it will remember the first MAC address it receives on port 2, and allow only packets from the learned MAC address on port 2:

hub ethernet 0 2
source-address

Related Commands

Command
Description

hub

Enables and configures a port on an Ethernet hub of a Cisco 2505 or Cisco 2507.


speed

To configure the speed for a Fast Ethernet interface, use the speed interface configuration command. Use the no form of this command to disable a speed setting.

speed {10 | 100 | auto}

no speed

Syntax Description

10

Configures the interface to transmit at 10 Mbps.

100

Configures the interface to transmit at 100 Mbps.

auto

Turns on the Fast Ethernet auto-negotiation capability. The interface automatically operates at 10 or 100 Mbps depending on environmental factors, such as the type of media and transmission speeds for the peer routers, hubs, and switches used in the network configuration.


Defaults

100 Mbps

Command Modes

Interface configuration

Command History

Release
Modification

11.2(10)P

This command was introduced.


Usage Guidelines

The auto negotiation capability is turned on for the Fast Ethernet interface by either configuring the speed auto interface configuration command or the duplex auto interface configuration command.

Table 58 describes the system's performance for different combinations of the duplex and speed modes. The specified duplex command configured with the specified speed command produces the resulting system action.

Table 58 Relationship between Duplex and Speed Commands 

Duplex Command
Speed Command
Resulting System Action

duplex auto

speed auto

Auto negotiates both speed and duplex modes.

duplex auto

speed 100 or speed 10

Auto negotiates both speed and duplex modes.

duplex half or duplex full

speed auto

Auto negotiates both speed and duplex modes.

duplex half

speed 10

Forces 10 Mbps and half duplex.

duplex full

speed 10

Forces 10 Mbps and full duplex.

duplex half

speed 100

Forces 100 Mbps and half duplex.

duplex full

speed 100

Forces 100 Mbps and full duplex.


Examples

The following example shows the configuration options for the speed command:

router# configure terminal 
Enter configuration commands, one per line.  End with CNTL/Z.
router(config)# interface fastethernet 0
router(config-if)# speed ?
  10    Force 10 Mbps operation
  100   Force 100 Mbps operation
  auto  Enable AUTO speed configuration

Related Commands

Command
Description

duplex

Configures the duplex operation on an interface.

interface fastethernet

Selects a particular Fast Ethernet interface for configuration.

show controllers fastethernet

Displays information about initialization block information, transmit ring, receive ring, and errors for the Fast Ethernet controller chip on the Cisco 4500, Cisco 7200 series, or Cisco 7500 series routers.

show interfaces fastethernet

Displays information about the FastEthernet interfaces.


squelch

To extend the Ethernet twisted-pair 10BaseT capability beyond the standard 100 meters on the Cisco 4000 platform, use the squelch interface configuration command. To restore the default, use the no form of this command.

squelch {normal | reduced}

no squelch {normal | reduced}

Syntax Description

normal

Allows normal capability.

reduced

Allows extended 10BaseT capability.


Defaults

Normal range

Command Modes

Interface configuration

Command History

Release
Modification

10.0

This command was introduced.


Examples

The following example extends the twisted-pair 10BaseT capability on the cable attached to Ethernet interface 2:

interface ethernet 2 
 squelch reduced

t1 bert

To enable or disable a BERT test pattern for a T1 channel on the Channelized T3 Interface Processor (CT3IP) in Cisco 7500 series routers, use the t1 bert controller configuration command. To disabled a BERT test pattern, use the no form of this command.

t1 channel bert pattern {0s | 1s | 2^15 | 2^20 | 2^23} interval minutes

no t1 channel bert pattern {0s | 1s | 2^15 | 2^20 | 2^23} interval minutes

Syntax Description

channel

Number between 1 and 28 that indicates the T1 channel.

pattern

Specifies the length of the repeating BERT test pattern. Values are:

0s

0s—Repeating pattern of zeros (...000...).

1s

1s—Repeating pattern of ones (...111...).

2^15

2^15—Pseudo-random repeating pattern that is 32767 bits in length.

2^20

2^20—Pseudo-random repeating pattern that is 1048575 bits in length.

2^23