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The commands shown in this chapter apply to the Catalyst 8540 MSR, Catalyst 8510 MSR, and LightStream 1010 ATM switch routers. Where an entire command or certain attributes of a command have values specific to a particular switch or switch router, an exception is indicated by the following callouts:
 |
Note Commands that are identical to those documented in the Cisco IOS software documentation have been removed from this chapter. |
|
Note Commands that no longer function as expected in ATM environments have also been removed from this chapter. |
Refer to Appendix D of this command reference for a detailed list of commands that have been removed, changed or replaced.
Syntax Description
optimistic Tag binding is returned immediately and packets are discarded until the downstream setup is complete. conservative Waits until the tag VC is set up downstream before returning a tag binding.
Defaults
conservative
Command Modes
Global configuration
Command History
11.3(3a) New command
Release
Modification
Examples
The following example sets the mode for handling binding requests to optimistic on TC ATM interfaces.
Switch# configure terminal Switch(config)# tag-switching atm allocation-mode optimistic
To configure the VPI/VCI to be used for the initial link to the tag switching peer, use the tag-switching atm control-vc interface configuration command. This control VC is used to establish the TDP session and carry non-IP traffic. To set the control VPI/VCI to the default, use the no form of this command.
tag-switching atm control-vc vpi vci
Syntax Description
vpi Virtual path identifier, in the range of 0 to 255. vci Virtual channel identifier, in the range of 1 to 65535.
Defaults
0/32
Command Modes
Interface configuration
Command History
11.3(3a) New command
Release
Modification
Usage Guidelines
On a VP tunnel, the default VPI is the tunnel number and the default VCI is 32.
Examples
The following example shows how to select VPI 1 and VCI 34 as the control VC.
Switch# configure terminal Switch(config)# interface atm 3/0/1 Switch(config-if)# tag-switching ip Switch(config-if)# tag-switching atm control-vc 1 34
Related Commands
Enables tag switching of IPv4 packets on an interface.
Command
Description
To control whether VC-merge (multipoint-to-point VCs) is supported for unicast tag VCs, use the tag-switching atm vc-merge global configuration command. To disable this feature, use the no form of this command.
tag-switching atm vc-mergeSyntax Description
This command has no keywords or arguments.
Defaults
Enabled
Command Modes
Global configuration
Command History
11.3(3a) New command
Release
Modification
Usage Guidelines
This feature is enabled by default.
Examples
Because this feature is enabled by default, it is not necessary to issue the tag-switching atm vc-merge command. However, to disable VC merge, you must enter the no form of the command.
Switch# configure terminal Switch(config)# no tag-switching atm vc-merge
Related Commands
Displays the requested entries from the ATM TDP tag binding database. Displays the ATM TDP tag capabilities for all interfaces.
Command
Description
Syntax Description
vpi Low end of the VPI range (0 to 255). - vpi High end of the VPI range (2 to 255).
Defaults
1 - 1
Command Modes
Interface configuration
Command History
11.3(3a) New command
Release
Modification
Usage Guidelines
The value will be negotiated with its peer.
You cannot enter a VPI range on a VP tunnel; the VPI is the PVP number of the tunnel.
If the TDP neighbor is a router, the VPI range cannot be larger than 2; for example, from 5 to 6
(a range of 2), not 5 to 7 (a range of 3).
Examples
The following example shows you how to select a VPI range from 5 to 6.
Switch# configure terminal Switch(config)# interface atm 3/0/1 Switch(config-if)# tag-switching ip Switch(config-if)# tag-switching atm vpi 5 - 6
To allow tag switching of IPv4 packets, use the tag-switching ip global configuration command.
To disable IP tag switching across all interfaces, use the no form of this command.
Syntax Description
This command has no keywords or arguments.
Defaults
Enabled
Command Modes
Global configuration
Command History
11.3(3a) New command
Release
Modification
Usage Guidelines
Dynamic tag switching (that is, the distribution of tags based on routing protocols) is allowed by this optional command, but is not actually enabled until the interface-level tag-switching ip command is issued on at least one interface.
The no form of this command stops the distribution of dynamic tags and the sending of outgoing tagged packets on all interfaces. The sending of tagged packets on TSP tunnels is not affected by this command.
For TC ATM, the no form of this command prevents tag VCs beginning at, terminating at, or passing through the platform.
Examples
The following example shows how to enable the distribution of dynamic tags on all interfaces.
Switch# configure terminal Switch(config)# tag-switching ip
Related Commands
Enables tag switching of IPv4 packets on an interface.
Command
Description
To enable tag switching of IPv4 packets on an interface, use the tag-switching ip interface configuration command. To disable IP tag switching on an interface, use the no form of this command.
tag-switching ipSyntax Description
This command has no keywords or arguments.
Defaults
Disabled
Command Modes
Interface configuration
Command History
11.3(3a) New command
Release
Modification
Usage Guidelines
The first time this command is issued on any interface, dynamic tag switching is enabled on the entire switch router. TDP Hellos are issued on this interface. When an outgoing tag for a destination routed out through this interface is received, packets sent to that destination are tagged as outgoing.
The no form of this command causes packets routed out through this interface to be sent as untagged, and outgoing TDP Hellos are no longer sent.
When the no form is issued on the only interface for which tag switching is enabled, dynamic tag switching is disabled on the entire switch router.
For TC ATM, the no form of this command prevents tag VCs beginning at, terminating at, or passing through the interface.
Examples
In the following example, tag switching is enabled on ATM interface 1/1/0.
Switch# configure terminal Switch(config)# interface atm 1/1/0 Switch(config-if)# tag-switching ip
Related Commands
Controls the mode used for handling tag binding requests on TC ATM interfaces. Enables tag switching of IPv4 packets.
Command
Description
To configure the interval between transmission of TDP discovery Hello messages and the hold time for a TDP transport connection, use the tag-switching tdp discovery global configuration command. To set the interval and hold time to their defaults, use the no form of this command.
tag-switching tdp discovery {hello | directed-hello} {holdtime | interval} seconds
Syntax Description
hello Intervals and hold times for directly connected neighbors. directed-hello Intervals and hold times for neighbors that are not directly connected; for example, TDP sessions that run over a TSP tunnel. holdtime Interval for which a connection stays up if no Hello messages are received. The default is 15 seconds. interval Period between sending Hello messages. The default is 5 seconds. seconds Hold time or interval, in the range of 1 to 2147483647.
Defaults
See "Syntax Description."
Command Modes
Global configuration
Command History
11.3(3a) New command
Release
Modification
Examples
In the following example, the interval for which a connection stays up if no Hello packets are received is set to 5 seconds.
Switch# configure terminal Switch(config)# tag-switching tdp discovery hello holdtime 5
Related Commands
Displays information about interfaces that have tag switching enabled. Displays summary information on ATM tag bindings. Displays available TDP parameters.
Command
Description
To configure the hold time for a TDP session, use the tag-switching tdp holdtime global configuration command. To set the hold time to the default, use the no form of this command.
tag-switching tdp holdtime seconds
Syntax Description
seconds The time, in seconds, that a TDP session is maintained in the absence of TDP messages from the session peer (1 to 2147483647).
Defaults
15 seconds
Command Modes
Global configuration
Command History
11.3(3a) New command
Release
Modification
Usage Guidelines
When a TDP session is initiated, the hold time is negotiated to the lower of the values configured at the two ends.
This command configures the hold time determined by this tag switch.
Examples
The following example configures the hold time of TDP sessions to 30 seconds.
Switch# configure terminal Switch(config)# tag-switching tdp holdtime 30
Related Commands
Displays available TDP parameters.
Command
Description
To enable support for TSP tunnel negotiation, use the tag-switching tsp-tunnels global configuration command or interface configuration command. To disable support for TSP tunnel negotiation, use the no form of this command.
tag-switching tsp-tunnelsSyntax Description
This command has no keywords or arguments.
Defaults
Disabled
Command Modes
Global configuration
Interface configuration
Command History
11.3(3a) New command
Release
Modification
Usage Guidelines
Enabling TSP tunnel negotiation using the tag-switching tsp-tunnels command in the interface configuration mode has no effect unless the command is also issued in the global configuration mode.
Examples
The following example shows how to enable TSP tunnel negotiation globally, then enable it at the interface.
Switch# configure terminal Switch(config)# tag-switching tsp-tunnels Switch(config)# interface atm 1/1/1 Switch(config-if)# tag-switching tsp-tunnels
Related Commands
Displays TSP tunnel status and configuration.
Command
Description
To specify that the switch or Flash device operates as a TFTP server, use the tftp-server global configuration commands. To remove a previously defined filename, use the no form of this command with the appropriate filename.
tftp-server device:filename [alias name] [ip-access-list]
Syntax Description
device: Specifies TFTP service of a file on a memory device. The colon (:) is required. Valid devices include the following: filename Name of a file that the TFTP server uses in answering TFTP Read Requests. alias Specifies an alternate name for the file that the TFTP server uses in answering TFTP Read Requests. ip-access-list IP access list of requesting hosts.
Defaults
Disabled
Command Modes
Global configuration
Command History
11.1(4) New command
Release
Modification
Usage Guidelines
You can specify multiple filenames by repeating the tftp-server command. The system sends a copy of the system image contained in memory to any client that issues a TFTP Read Request with this filename.
If the specified filename exists in memory, a copy of the image is sent.
Images that run from ROM cannot be loaded over the network. Therefore, you should not use TFTP to offer the ROMs on these images.
The system sends a copy of the file to any client that issues a TFTP Read Request with its filename.
Examples
In the following example, the system uses TFTP to send a copy of the version-11.1 file located in Flash memory in response to a TFTP Read Request for that file. The requesting host is checked against access list 22.
Switch# configure terminal Switch(config)# tftp-server flash version-11.1 22
In the following example, the system uses TFTP to send a copy of the version-11.1.4 file in response to a TFTP Read Request for that file. The file is located on the Flash memory card inserted in slot 0 of the route processor card.
Switch# configure terminal Switch(config)# tftp-server flash slot0:version-11.1.4
Related Commands
Defines an extended IP access list. Currently, this command only supports the IP host.
Command
Description
To configure the PNNI timers, use the timer PNNI node configuration command. To return to the default values, use the no form of this command.
timer [ack delay tenths-of-seconds] [called-integrity seconds] [calling-integrity seconds] [hello-holddown tenths-of-seconds] [hello-interval seconds] [hrz-link-inactivity seconds] [inactivity-factor number] [retransmit-interval seconds]
Syntax Description
ack-delay Specifies the waiting period before sending an accumulated PTSE acknowledgment packet. The default is 1 second. called-integrity Specifies the value used to initialize the SVC integrity timer at the node that accepts an LGN-to-LGN SVC RCC originated by a neighbor node. The default is 50 seconds. calling-integrity Specifies the value used to initialize the SVC integrity timer at the node that initiates an LGN-to-LGN SVC RCC. The SVC integrity timer determines how long this node waits for an SVC-based RCC to reach the two-way inside state before releasing it. The default is 35 seconds. hello-holddown Specifies the hold-down period for event-triggered Hellos. This is mainly used for Hello packets between outside neighbors. The default is 1 second. hello-interval Specifies the frequency, in seconds, at which Hello packets are transmitted. The default is 15 seconds. hrz-link-inactivity Specifies the length of time that this node continues to advertise a horizontal link for which it has not received and processed an LGN horizontal link extension information group piggybacked onto an SVC-RCC Hello packet. The default is 120 seconds. inactivity-factor Specifies the dead-interval time (the period after which a neighbor is declared down if no Hello is received) as a factor of the Hello interval. The default is 5 seconds. retransmit-interval Specifies the waiting period before retransmitting a PTSE, PTSE request, or database summary packet. The default is 5 seconds.
Defaults
See "Syntax Description."
Command Modes
PNNI node configuration
Command History
11.1(4) New command
Release
Modification
Usage Guidelines
Decreasing the hello-interval allows PNNI to detect neighbor nodes that have stopped functioning more quickly. The inactivity-factor is used as a multiplier of the hello interval in received Hello packets to determine the dead interval, the time after which the neighbor node is declared down if no Hello packets are received. The inactivity-factor can be increased on unreliable interfaces to avoid false alarms.
Decreasing the retransmit-interval causes retransmission to increase when a PNNI packet gets lost. However, this increases the risk of unnecessarily retransmitting PNNI packets that are delayed but actually reach the neighbor. Increasing ack-delay causes more PTSEs to be acknowledged in one ack packet. Lowering hello-holddown allows another Hello packet to be sent shortly after one was sent. To avoid an overload in switch processing, you should adjust these parameters carefully.
For more information, refer to the ATM Switch Router Software Configuration Guide.
Examples
The following script shows how to change the hello-interval to 5 seconds.
Switch# configure terminal Switch(config)# atm router pnni Switch(config-atm-router)# node 1 Switch(config-pnni-node)# timer hello-interval 5
Related Commands
Displays information about a PNNI logical node running on the switch.
Command
Description
To trace the IP routes the packets actually take when traveling from the switch to their destination, use the traceroute EXEC command.
traceroute [protocol] [destination]
Syntax Description
protocol Protocol that can be used is ip. destination Destination address or host name on the command line. The default parameters for the appropriate protocol are assumed, and the tracing action begins.
Defaults
The protocol argument is based on the switch router's examination of the format of the destination argument. For example, if the switch router finds a destination in IP format, the protocol defaults to ip.
Command Modes
EXEC
Command History
12.0(10)W5(18) Re-introduced into this manual. (Was previously in the LightStream 1010 Command Reference only.)
Release
Modification
Usage Guidelines
The traceroute command works by taking advantage of the error messages generated by switch routers when a datagram exceeds its TTL value.
The traceroute command starts by sending probe datagrams with a TTL value of 1. This causes the first switch router to discard the probe datagram and send back an error message. The traceroute command sends several probes at each TTL level and displays the round-trip time for each.
The traceroute command sends out one probe at a time. Each outgoing packet may result in one or two error messages. A "time exceeded" error message indicates that an intermediate switch router detected and discarded the probe. A "destination unreachable" error message indicates that the destination node received and discarded the probe because it could not deliver the packet. If the timer goes off before a response comes in, traceroute prints an asterisk(*).
The traceroute command terminates when the destination responds, when the maximum TTL is exceeded, or when the user interrupts the trace with the escape sequence. By default, to invoke the escape sequence, enter ^X.
Common Trace Problems
Due to bugs in the IP implementation of various hosts and switches, the IP trace command may behave in unexpected ways.
Not all destinations respond correctly to a probe message by sending back an "ICMP port unreachable" message. A long sequence of TTL levels with only asterisks, terminating only when the maximum TTL is reached, may indicate this problem.
There is a known problem with the way some hosts handle an "ICMP TTL exceeded" message. Some hosts generate in ICMP message, but they reuse the TTL of the incoming packet. Since this is zero, the ICMP packets do not make it back. When you trace the path to such a host, you may see a set of TTL values with asterisks (*). Eventually, the TTL gets high enough that the "ICMP" message can get back. For example, if the host is 6 hops away, traceroute times out in responses 6 through 11.
Examples
The following example displays sample IP traceroute output when a destination host name is specified:
Switch# traceroute ip ABA.NYC.mil
Type escape sequence to abort.
Tracing the route to ABA.NYC.mil (26.0.0.73)
1 DEBRIS.CISCO.COM (131.108.1.6) 1000 msec 8 msec 4 msec
2 BARRNET-GW.CISCO.COM (131.108.16.2) 8 msec 8 msec 8 msec
3 EXTERNAL-A-GATEWAY.STANFORD.EDU (192.42.110.225) 8 msec 4 msec 4 msec
4 BB2.SU.BARRNET.NET (131.119.254.6) 8 msec 8 msec 8 msec
5 SU.ARC.BARRNET.NET (131.119.3.8) 12 msec 12 msec 8 msec
6 MOFFETT-FLD-MB.in.MIL (192.52.195.1) 216 msec 120 msec 132 msec
7 ABA.NYC.mil (26.0.0.73) 412 msec 628 msec 664 msec
Table 19-1 describes the fields shown in the display.
| Field | Description |
|---|---|
1 | Indicates the sequence number of the switch router in the path to the host. |
DEBRIS.CISCO.COM | Host name of this switch router. |
131.108.1.61 | IP address of this switch router. |
1000 msec 8 msec 4 mesc | Round-trip time for each of the three probes that are sent. |
Table 19-2 describes the characters that can appear in traceroute output.
| Character | Description |
|---|---|
nn msec | For each node, the round-grip time in milliseconds for the specified number of probes. |
* | The probe timed out. |
? | Unknown packet type. |
Q | Source quench. |
P | Protocol unreachable. |
N | Network unreachable. |
U | Port unreachable. |
H | Host unreachable. |
Related Commands
See Appendix D.
Command
Description
To indicate to the network that this node does not allow calls to transit through, use the transit-restricted PNNI node configuration command. To allow calls to transit through the node,
use the no form of this command.
Syntax Description
This command has no keywords or arguments.
Defaults
Enabled
Command Modes
PNNI node configuration
Command History
11.1(4) New command
Release
Modification
Usage Guidelines
This command enables the network administrator to prevent connections from transiting nodes that only originate or terminate connections, for example, low-end edge switches that do not have the capacity to support transit calls.
For more information, refer to the ATM Switch Router Software Configuration Guide.
Examples
The following script shows how to access the transit-restricted PNNI node configuration command.
Switch# configure terminal Switch(config)# atm router pnni Switch(config-atm-router)# node 1 Switch(config-pnni-node)# transit-restricted
Related Commands
Displays information about a PNNI logical node running on the switch.
Command
Description
To configure T1 framing mode, use the t1 framing controller configuration command.
t1 line-number framing {esf | sf}
Syntax Description
line-number Specifies a T1 line, from 1 to 28. esf Specifies that extended super frame is used as the T1 framing type. sf Specifies that super frame is used as the T1 framing type.
Defaults
esf
Command Modes
Controller configuration
Command History
12.0(3c)W5(9) New command
Release
Modification
Usage Guidelines
Use the t1 framing controller configuration command to specify the framing mode used by the t1 line.
Examples
The following example sets the framing mode on the t1 interface on line 1 to esf and on line 2 to sf.
Switch# configure terminal Switch(config)# controller t3 3/1/0 Switch(config-controller)# t1 1 framing esf Switch(config-controller)# t1 2 framing sf
To configure T1 autoalarm detection and generation, use the t1 yellow controller configuration command. To disable autoalarm detection and generation, use the no form of this command.
t1 line-number yellow {generation | detection}
Syntax Description
line-number Specifies a T1 line, from 1 to 28. generation Generates yellow alarms. detection Detects yellow alarms.
Defaults
Yellow alarms are detected and generated on the T1 channel.
Command Modes
Controller configuration
Command History
12.0(3c)W5(9) New command
Release
Modification
Usage Guidelines
A yellow alarm indicates a loss of frame alignment at the remote end. Use the t1 yellow command to turn the generation or detection of yellow alarms on or off.
|
Note If you use the t1 framing command to select the sf framing mode, you should consider turning off alarm detection because the yellow alarms might be detected incorrectly with sf framing enabled. |
Examples
The following example enables autoalarm detection.
Switch# configure terminal Switch# (config)# controller t3 1/1/0 Switch# (config-controller)# t1 1 yellow detection
Related Commands
Displays information about a physical port device.
Command
Description
Posted: Wed Sep 6 15:41:25 PDT 2000
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