|
|
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. |
Conservative
Global configuration
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 vcivpi | Virtual path identifier, in the range of 0 to 255. |
vci | Virtual channel identifier, in the range of 1 to 65,535. |
0/32
Interface configuration
On a VP tunnel, the default VPI is the tunnel number and the default VCI is 32.
The following example shows how to select VPI 1 and VCI 34 as the control VC.
Switch(config)# interface atm 3/0/1 Switch(config-if)# tag-switching ip Switch(config-if)# tag-switching atm control-vc 1 34
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-mergeThis command has no keywords or arguments.
Enabled.
Global configuration
Since the default mode is to enable VC merge, 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(config)# no tag-switching atm vc-merge
show tag-switching atm-tdp bindings
show tag-switching atm-tdp capability
vpi | Low end of the VPI range (1 to 255). |
- vpi | High end of the VPI range (1 to 255). |
1 - 1
Interface configuration
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).
The following example shows you how to select a VPI range from 5 to 6.
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.
tag-switching ipThis command has no keywords or arguments.
Enabled
Global configuration
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.
The following example shows how to enable the distribution of dynamic tags on all interfaces.
Switch# configure terminal Switch(config)# tag-switching ip
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 ipThis command has no keywords or arguments.
Disabled
Interface configuration
The first time this command is issued on any interface, dynamic tag switching is enabled on the entire switch. 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.
For TC ATM, the no form of this command prevents tag VCs beginning at, terminating at, or passing through the this interface.
In the following example, tag switching is enabled on ATM interface 1/1/0.
Switch(config)# interface atm 1/1/0 Switch(config-if)# tag-switching ip
tag-switching atm allocation-mode
tag-switching ip (global)
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} secondshello | 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. |
See the syntax descriptions.
Global configuration
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
show tag-switching interfaces
show tag-switching atm-tdp summary
show tag-switching tdp parameters
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 secondsseconds | The time, in seconds, that a TDP session is maintained in the absence of TDP messages from the session peer (1 to 2147483647). |
15 seconds
Global configuration
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.
The following example configures the hold time of TDP sessions to 30 seconds.
Switch# configure terminal Switch(config)# tag-switching tdp holdtime 30
show tag-switching tdp parameters
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-tunnelsThis command has no keywords or arguments.
Disabled
Global configuration
Interface configuration
Enabling TSP tunnel negotiation using the tag-switching tsp-tunnels command in the interface configuration mode has no effect unless command is also issued in the global configuration mode.
The following example shows how to enable TSP tunnel negotiation globally, then enable it at the interface.
Switch(config)# tag-switching tsp-tunnels Switch(config)# interface atm 1/1/1 Switch(config-if)# tag-switching tsp-tunnels
show tag-switching tsp-tunnels
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 flash [device:] filename1 [alias filename2] [rom alias filename2] [atm-accounting
flash | Specifies TFTP service of a file in Flash memory. |
device: | Specifies TFTP service of a file on a Flash memory device. The colon (:) is required. Valid devices are as follows: · bootflash: This device is the internal Flash memory. · slot0: This device is the first PCMCIA slot on the route processor card. · slot1: This device is the second PCMCIA slot on the route processor card. |
filename1 | Name of a file in Flash or in ROM 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. |
filename2 | Alternate name of the file that the TFTP server uses in answering TFTP Read Requests. A client of the TFTP server can use this alternate name in its Read Requests. |
atm-accounting | Specifies the name of the file the TFTP server uses in answering TFTP Read Requests. |
filename3 | Alternate name of the file that the TFTP server uses in answering TFTP Read Requests. A client of the TFTP server can use this alternate name in its Read Requests. |
Disabled
Global configuration
You can specify multiple filenames by repeating the tftp-server command. The system sends a copy of the system image contained in ROM or one of the system images contained in Flash memory to any client that issues a TFTP Read Request with this filename.
If the specified filename1 or filename2 exists in Flash memory, a copy of the Flash image is sent. On systems that contain a complete image in ROM, the system sends the ROM image if the specified filename1 or filename2 is not found in Flash memory.
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 contained on one of the Flash memory devices to any client that issues a TFTP Read Request with its filename.
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(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(config)# tftp-server flash slot0:version-11.1.4
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]
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 SVCC integrity timer at the node that accepts an LGN-to-LGN SVCC 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 SVCC RCC. The SVC integrity timer determines how long this node will wait for an SVCC-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 will continue to advertise a horizontal link for which it has not received and processed an LGN horizontal link extension information group piggybacked onto an SVCC-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. |
See the syntax descriptions.
PNNI node configuration
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 reaches 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 Catalyst 8540 MSR Software Configuration Guide.
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
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.
transit-restrictedThis command has no keywords or arguments.
Enabled
PNNI node configuration
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 Catalyst 8540 MSR Software Configuration Guide.
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
Posted: Thu Sep 2 10:33:35 PDT 1999
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