Table Of Contents
show ip traffic-engineering configuration
show ip traffic-engineering routes
show tag-switching atm-tdp bindings
show tag-switching atm-tdp capability
show tag-switching atm-tdp summary
show tag-switching forwarding-table
show tag-switching tdp bindings
show tag-switching tdp discovery
show tag-switching tdp neighbors
show tag-switching tdp parameters
show tag-switching tsp-tunnels
tag-switching atm allocation-mode
tag-switching ip (global configuration)
tag-switching ip (interface configuration)
tag-switching ip default-route
tag-switching tag-range downstream
tag-switching tsp-tunnels (global configuration)
tag-switching tsp-tunnels (interface configuration)
Tag Switching Commands
This chapter documents commands used to configure Tag Switching features in Cisco IOS software. For guidelines on configuring Tag Switching features, refer to the Cisco IOS Switching Services Configuration Guide.
Note
Beginning with Cisco IOS Release 11.3, all commands supported on the Cisco 7500 series routers are also supported on Cisco 7000 series routers.
show ip traffic-engineering
To display information about the traffic engineering configuration and metric information associated with it, use the show ip traffic-engineering privileged EXEC command.
show ip traffic-engineering [metrics [detail]]
Syntax Description
metrics
(Optional) Displays metric information associated with traffic engineering.
detail
(Optional) Displays information in long form.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The goal of the loop prevention algorithm is that traffic should not be sent down the tunnel if there is a possibility that, after leaving the tunnel, steady state routing will route the traffic back to the head of the tunnel.
The approach of the loop prevention algorithm is to compare the Layer 3 routing distance to the egress from the tunnel tailend and tunnel headend. The loop check passes only if the tunnel tail is closer to the egress than the tunnel head is.
The loop prevention algorithm allows you to use the tunnel for a route if one the following cases applies:
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The loop prevention algorithm prevents you from using the tunnel for a given egress in all other cases. In particular, when
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Devices request metrics via a TDP adjacency. The display output shows detailed metric information.
The metric information includes a metric type (shown as routing_protocol/routing_protocol_subtype) and a metric value.
The routing protocol is as follows:
OSPF
IS-IS
EIGRP
Connected
Static
Other (some other routing protocol)The routing protocol subtype is specific to each routing protocol.
Examples
The following is sample output from the show ip traffic-engineering metrics detail command:
Router# show ip traffic-engineering metrics detailMetrics requested BY this devicePrefix 43.0.0.1/32TDP id 2.2.2.2:0, metric: connected/0type request, flags metric-received, rev 6, refcnt 1TDP id 4.4.4.4:0, metric: ospf-300/2type request, flags metric-received, rev 7, refcnt 1Prefix 44.0.0.0/8TDP id 18.18.18.18:0, metric: connected/0type request, flags metric-received, rev 1, refcnt 1Metrics requested FROM this devicePrefix 36.0.0.0/8TDP id 18.18.18.18:0, metric: connected/0type advertise, flags none, rev 1, refcnt 1Table 102 defines the fields displayed in the first three lines of this display.
Related Commands
Uses the traffic-engineering filter command.
Configures a route for a specified filter, through a specified tunnel.
show ip traffic-engineering configuration
To display information about configured traffic engineering filters and routes, use the show ip traffic-engineering configuration privileged EXEC command.
show ip traffic-engineering configuration [interface] [filter-number] [detail]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The sample output can show all filters or can be limited by interface, filter number, or both.
Examples
The following is sample output from the show ip traffic-engineering configuration detail command:
Router# show ip traffic-engineering configuration detailTraffic Engineering ConfigurationFilter 5: egress 44.0.0.0/8, local metric: ospf-0/1Tunnel5 route installedinterface up, preference 1loop check on, passing, remote metric: connected/0Filter 6: egress 43.0.0.1/32, local metric: ospf-300/3Tunnel7 route installedinterface up, preference 50loop check on, passing, remote metric: ospf-300/2Tunnel6 route not installedinterface up, preference 75loop check on, passing, remote metric: connected/0Table 103 describes the fields displayed in the first four lines of this display.
Related Commands
Displays information about the requested filters configured for traffic engineering.
show ip traffic-engineering routes
To display information about the requested filters configured for traffic engineering, use the show ip traffic-engineering routes privileged EXEC command.
show ip traffic-engineering routes [filter-number] [detail]
Syntax Description
filter-number
(Optional) A decimal value representing the number of the filter to display.
detail
(Optional) Display of command output in long form.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Requests can be limited to a specific filter.
Examples
The following is sample output from the show ip traffic-engineering routes command:
Router# show ip traffic-engineering routesInstalled traffic engineering routes:Codes: T - traffic engineered routeT 43.0.0.1/32 (not override of routing table entry)is directly connected, 00:06:35, Tunnel7T 44.0.0.0/8 (override of routing table entry)is directly connected, 01:12:39, Tunnel5Table 104 describes the significant fields in this display.
Related Commands
show tag-switching atm-tdp bindings
To display the requested entries from the ATM TDP tag binding database, use the show tag-switching atm-tdp bindings privileged EXEC command. The ATM TDP database contains TIB entries for tag VCs on TC-ATM interfaces.
show tag-switching atm-tdp bindings [network {mask | length}] [local-tag vpi vci ][remote-tag vpi vci] [neighbor interface]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The display output can show entries from the entire database, or it can be limited to a subset of entries based on prefix, VC tag value, and/or an assigning interface.
Examples
The following is router sample output from the show tag-switching atm-tdp bindings command:
Router# show tag-switching atm-tdp bindingsDestination: 10.16.0.16/32Tailend Router ATM1/0.1 1/35 1/34 Active, VCD=2Destination: 10.24.0.0/24Tailend Router ATM1/0.1 1/39 Active, VCD=3Destination: 10.15.0.15/32Tailend Router ATM1/01 1/33 Active, VCD=4Destination: 10.23.0 0/24Tailend Router ATM1/01 1/37 Active, VCD=5Table 105 describes the significant fields in this display.
The following is ATM switch sample output from the show tag-switching atm-tdp bindings command:
Switch# show tag-switching atm-tdp bindingsDestination: 6.6.6.6/32Tailend Switch ATM0/0/3 1/34 Active -> Terminating ActiveDestination: 150.0.0.0/16Tailend Switch ATM0/0/3 1/35 Active -> Terminating ActiveDestination: 4.4.4.4/32Transit ATM0/0/3 1/33 Active -> ATM0/1/1 1/33 ActiveRelated Commands
show tag-switching atm-tdp capability
To display the ATM TDP tag capabilities, use the show tag-switching atm-tdp capability privileged EXEC command.
show tag-switching atm-tdp capability
Syntax Description
This command has no arguments or keywords.
Command Modes
Privileged EXEC
Command History
Examples
The following example shows the display from the show tag-switching atm-tdp capability command.
Router# show tag-switching atm-tdp capabilityVPI VCI Alloc Odd/Even VC MergeATM0/1/0 Range Range Scheme Scheme IN OUTNegotiated [100 - 101] [33 - 1023] UNIDIR - -Local [100 - 101] [33 - 16383] UNIDIR EN ENPeer [100 - 101] [33 - 1023] UNIDIR - -VPI VCI Alloc Odd/Even VC MergeATM0/1/1 Range Range Scheme Scheme IN OUTNegotiated [201 - 202] [33 - 1023] BIDIR - -Local [201 - 202] [33 - 16383] UNIDIR ODD NO NOPeer [201 - 202] [33 - 1023] BIDIR EVEN - -Table 106 lists the significant fields in this display.
Related Commands
show tag-switching atm-tdp summary
To display summary information on ATM tag bindings, use the show tag-switching atm-tdp summary privileged EXEC command.
show tag-switching atm-tdp summary
Syntax Description
This command has no arguments or keywords.
Command Modes
Privileged EXEC
Command History
Examples
The following is sample output from the show tag-switching atm-tdp summary command:
Router# show tag-switching atm-tdp summaryTotal number of destinations: 788TC-ATM bindings summary interface total active bindwait local remote other ATM0/0/0 594 592 1 296 298 1 ATM0/0/1 590 589 0 294 296 1 ATM0/0/2 1179 1178 0 591 588 1 ATM0/0/3 1177 1176 0 592 585 1 ATM0/1/0 1182 1178 4 590 588 0 Waiting for bind on ATM0/0/0 10.21.0.0/24Table 107 describes the significant fields in this display.
Related Commands
show tag-switching forwarding-table
To display the contents of the Tag Forwarding Information Base (TFIB), use the show tag-switching forwarding-table privileged EXEC command.
show tag-switching forwarding-table [{network {mask | length} | tags tag [- tag] | interface interface | next-hop address | tsp-tunnel [tunnel-id ]}] [detail]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The optional parameters allow specification of a subset of the entire TFIB.
Examples
The following is sample output from the show tag-switching forwarding-table command:
Router# show tag-switching forwarding-tableLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface26 Untagged 10.253.0.0/16 0 Et4/0/0 172.27.32.428 1/33 10.15.0.0/16 0 AT0/0.1 point2point29 Pop tag 10.91.0.0/16 0 Hs5/0 point2point1/36 10.91.0.0/16 0 AT0/0.1 point2point30 32 10.250.0.97/32 0 Et4/0/2 10.92.0.732 10.250.0.97/32 0 Hs5/0 point2point34 26 10.77.0.0/24 0 Et4/0/2 10.92.0.726 10.77.0.0/24 0 Hs5/0 point2point35 Untagged [T] 10.100.100.101/32 0 Tu301 point2point36 Pop tag 168.1.0.0/16 0 Hs5/0 point2point1/37 168.1.0.0/16 0 AT0/0.1 point2point[T] Forwarding through a TSP tunnel.View additional tagging info with the 'detail' optionThe following is sample output from the show tag-switching forwarding-table command when you specify detail:
Router# show tag-switching forwarding-table detailLocal Outgoing Prefix Bytes tag Outgoing NextHoptag tag or VC or Tunnel Id switched interface26 Untagged 10.253.0.0/16 0 Et4/0/0 172.27.32.4MAC/Encaps=0/0, MTU=1504, Tag Stack{}28 1/33 10.15.0.0/16 0 AT0/0.1 point2pointMAC/Encaps=4/8, MTU=4470, Tag Stack{1/33(vcd=2)}00020900 0000200029 Pop tag 10.91.0.0/16 0 Hs5/0 point2pointMAC/Encaps=4/4, MTU=4474, Tag Stack{}FF0300811/36 10.91.0.0/16 0 AT0/0.1 point2pointMAC/Encaps=4/8, MTU=4470, Tag Stack{1/36(vcd=3)}00030900 0000300030 32 10.250.0.97/32 0 Et4/0/2 10.92.0.7MAC/Encaps=14/18, MTU=1500, Tag Stack{32}006009859F2A00E0F7E984828847 0002000032 10.250.0.97/32 0 Hs5/0 point2pointMAC/Encaps=4/8, MTU=4470, Tag Stack{32}FF030081 0002000034 26 10.77.0.0/24 0 Et4/0/2 10.92.0.7MAC/Encaps=14/18, MTU=1500, Tag Stack{26}006009859F2A00E0F7E984828847 0001A00026 10.77.0.0/24 0 Hs5/0 point2pointMAC/Encaps=4/8, MTU=4470, Tag Stack{26}FF030081 0001A00035 Untagged 10.100.100.101/32 0 Tu301 point2pointMAC/Encaps=0/0, MTU=1504, Tag Stack{}, via Et4/0/236 Pop tag 168.1.0.0/16 0 Hs5/0 point2pointMAC/Encaps=4/4, MTU=4474, Tag Stack{}FF0300811/37 168.1.0.0/16 0 AT0/0.1 point2pointMAC/Encaps=4/8, MTU=4470, Tag Stack{1/37(vcd=4)}00040900 00004000Table 108 describes the significant fields in this display.
show tag-switching interfaces
To display information about one or more interfaces that have Tag Switching enabled, use the show tag-switching interfaces privileged EXEC command.
show tag-switching interfaces [interface][detail]
Syntax Description
interface
(Optional) The interface about which to display Tag Switching information.
detail
(Optional) Displays information in long form.
Command Modes
EXEC
Command History
Usage Guidelines
You can show information about the requested interface or about all interfaces on which Tag Switching is enabled.
Examples
The following is sample output from the show tag-switching interfaces command:
Router# show tag-switching interfacesInterface IP Tunnel OperationalHssi3/0 Yes Yes NoATM4/0.1 Yes Yes Yes (ATM tagging)Ethernet5/0/0 No Yes YesEthernet5/0/1 Yes No YesEthernet5/0/2 Yes No NoEthernet5/0/3 Yes No YesEthernet5/1/1 Yes No No
Note
Table 109 describes the significant fields in this display.
The following is sample output from the show tag-switching interfaces command when you specify detail:
Router# show tag-switching interface Ethernet2/0/1 detailInterface Hssi3/0:IP tagging enabledTSP Tunnel tagging enabledTagging not operationalMTU = 4470Interface ATM4/0.1:IP tagging enabledTSP Tunnel tagging enabledTagging operationalMTU = 4470ATM tagging: Tag VPI = 1, Control VC = 0/32Interface Ethernet5/0/0:IP tagging not enabledTSP Tunnel tagging enabledTagging operationalMTU = 1500Interface Ethernet5/0/1:IP tagging enabledTSP Tunnel tagging not enabledTagging operationalMTU = 1500Interface Ethernet5/0/2:IP tagging enabledTSP Tunnel tagging not enabledTagging not operationalMTU = 1500Interface Ethernet5/0/3:IP tagging enabledTSP Tunnel tagging not enabledTagging operationalMTU = 1500Related Commands
Enables Tag Switching of IPv4 packets on an interface.
Allows TSP tunnel operation over an interface.
show tag-switching tdp bindings
To display the contents of the tag information base (TIB), use the show tag-switching tdp bindings privileged EXEC command:
show tag-switching tdp bindings [network {mask | length} [longer-prefixes]] [local-tag tag
[- tag]] [remote-tag tag [- tag]] [neighbor address] [local]Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
A request can specify that the entire database be shown, or it or can be limited to a subset of entries. A request to show a subset of entries can be based on the prefix, on input or output tag values or on ranges, and/or the neighbor advertising the tag.
Examples
The following is sample output from the show tag-switching tdp bindings command. This form of the command causes the contents of the entire TIB to be displayed.
Router# show tag-switching tdp bindingsMatching entries:tib entry: 10.92.0.0/16, rev 28local binding: tag: imp-null(1)remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 10.102.0.0/16, rev 29local binding: tag: 26remote binding: tsr: 172.27.32.29:0, tag: 26tib entry: 10.105.0.0/16, rev 30local binding: tag: imp-null(1)remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 10.205.0.0/16, rev 31local binding: tag: imp-null(1)remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 10.211.0.7/32, rev 32local binding: tag: 27remote binding: tsr: 172.27.32.29:0, tag: 28tib entry: 10.220.0.7/32, rev 33local binding: tag: 28remote binding: tsr: 172.27.32.29:0, tag: 29tib entry: 99.101.0.0/16, rev 35local binding: tag: imp-null(1)remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 100.101.0.0/16, rev 36local binding: tag: 29remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 171.69.204.0/24, rev 37local binding: tag: imp-null(1)remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 172.27.32.0/22, rev 38local binding: tag: imp-null(1)remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 210.10.0.0/16, rev 39local binding: tag: imp-null(1)tib entry: 210.10.0.8/32, rev 40remote binding: tsr: 172.27.32.29:0, tag: 27The following is sample output from the show tag tdp bindings 10.0.0.0 8 longer-prefixes neighbor 172.27.32.29 variant of the command; it displays tags learned from TSR 172.27.32.29 for network 10.0.0.0 and any of its subnets. The use of the neighbor option suppresses the output of local tags and tags learned from other neighbors.
Router# show tag tdp bindings 10.0.0.0 8 longer-prefixes neighbor 172.27.32.29tib entry: 10.92.0.0/16, rev 28remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 10.102.0.0/16, rev 29remote binding: tsr: 172.27.32.29:0, tag: 26tib entry: 10.105.0.0/16, rev 30remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 10.205.0.0/16, rev 31remote binding: tsr: 172.27.32.29:0, tag: imp-null(1)tib entry: 10.211.0.7/32, rev 32remote binding: tsr: 172.27.32.29:0, tag: 28tib entry: 10.220.0.7/32, rev 33remote binding: tsr: 172.27.32.29:0, tag: 29Table 110 describes the significant fields in this display.
Related Commands
show tag-switching tdp discovery
To display the status of the TDP discovery process, use the show tag-switching tdp discovery privileged EXEC command. Status means a list of interfaces over which TDP discovery is running.
show tag-switching tdp discovery
Syntax Description
This command has no arguments or keywords.
Command Modes
Privileged EXEC
Command History
Examples
The following is sample output from the show tag-switching tdp discovery command.
Router# show tag-switching tdp discoveryLocal TDP Identifier:172.27.32.29:0TDP Discovery Sources:Interfaces:ATM0/0.1: xmit/recvATM0/0.1: xmit/recEthernet4/0/1: xmit/recvEthernet4/0/2: xmit/recvPOS6/0/0: xmit/recvTable 111 describes the significant fields in this display.
Related Commands
show tag-switching tdp neighbors
To display the status of Tag Distribution Protocol (TDP) sessions, enter the show tag-switching tdp neighbors privileged EXEC command:
show tag-switching tdp neighbors [address | interface] [detail]
Syntax Description
address
(Optional) The neighbor with this IP address.
interface
(Optional) TDP neighbors accessible over this interface.
detail
(Optional) Displays information in long form.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The neighbor information branch can give information about all TDP neighbors, or it can be limited to
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•
Examples
The following is sample output from the show tag-switching tdp neighbors command:
Router# show tag-switching tdp neighborsPeer TDP Ident: 10.220.0.7:1; Local TDP Ident 172.27.32.29:1TCP connection: 10.220.0.7.711 - 172.27.32.29.11029State: Oper; PIEs sent/rcvd: 17477/17487; Downstream on demandUp time: 01:03:00TDP discovery sources:ATM0/0.1Peer TDP Ident: 210.10.0.8:0; Local TDP Ident 172.27.32.29:0TCP connection: 210.10.0.8.11004 - 172.27.32.29.711State: Oper; PIEs sent/rcvd: 14656/14675; DownstreamUp time: 2d5hTDP discovery sources:Ethernet4/0/1Ethernet4/0/2POS6/0/0Addresses bound to peer TDP Ident:99.101.0.8 172.27.32.28 10.105.0.8 10.92.0.810.205.0.8 210.10.0.8Table 112 describes the significant fields in this display.
Related Commands
show tag-switching tdp parameters
To display available TDP parameters, use the show tag-switching tdp parameters privileged EXEC command:
show tag-switching tdp parameters
Syntax Description
This command has no arguments or keywords.
Command Modes
Privileged EXEC
Command History
Examples
The following is sample output from the show tag-switching tdp parameters command:
Router# show tag-switching tdp parametersProtocol version: 1Downstream tag pool: min tag: 10; max_tag: 10000; reserved tags: 16Session hold time: 15 sec; keep alive interval: 5 secDiscovery hello: holdtime: 15 sec; interval: 5 secDiscovery directed hello: holdtime: 15 sec; interval: 5 secAccepting directed hellosTable 113 describes the significant fields in this display.
Related Commands
Configures the interval between transmission of TDP discovery hello messages.
Enables TSP tunnel functionality on a device.
show tag-switching tsp-tunnels
To display information about the configuration and status of selected tunnels, use the show tag-switching tsp-tunnels privileged EXEC command.
show tag-switching tsp-tunnels [{head | middle | tail | all | remote | address}
[interface-number]] [brief]Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The optional keywords restrict the set of tunnels displayed. With no optional keywords, the command displays all tunnels passing through the node.
Each TSP tunnel has a globally unique identifier. When signalling the TSP tunnel is signalled and is available at each hop, this identifier is used. This identifier is a combination of the originating IP address and the number of the Cisco IOS tunnel interface used in configuring the TSP tunnel at the headend.
Examples
The following is sample output from the show tag-switching tsp-tunnels command:
Signalling Summary:TSP Tunnels Process: runningRSVP Process: runningForwarding: enabledTUNNEL ID DESTINATION STATUS CONNECTION 10.106.0.6 0 10.2.0.12 up upTable 114 describes the significant fields in this display.
Related Commands
Allows TSP tunnel operation over an interface.
Sets the encapsulation mode of the tunnel to Tag Switching.
tag-switching advertise-tags
To control the distribution of locally assigned (incoming) tags via the Tag Distribution Protocol (TDP), use the tag-switching advertise-tags global configuration command. To disable tag advertisement, use the no form of this command.
tag-switching advertise-tags [for access-list-number [to access-list-number]]
no tag-switching advertise-tags [for access-list-number [to access-list-number]]
Syntax Description
Defaults
The tags of all destinations are advertised to all TSR neighbors.
Command Modes
Global configuration
Command History
Usage Guidelines
To enable the distribution of all locally assigned tags to all TDP neighbors, use the tag-switching advertise-tags command
You can enter multiple tag-switching advertise-tags commands. Taken together, they determine how local tags are advertised.
Note
Examples
In the following example, the router is configured to advertise all locally assigned tags to all TDP neighbors. This is the default.
Router(config)# tag-switching advertise-tagsIn the following example, the router is configured to advertise to all TDP neighbors tags for networks 10.101.0.0 and 10.221.0.0 only.
Router(config)# access-list 1 permit 10.101.0.0 0.0.255.255Router(config)# access-list 4 permit 10.221.0.0 0.0.255.255 Router(config)# tag-switching advertise-tags for 1 Router(config)# tag-switching advertise-tags for 4In the following example, the router is configured to advertise all tags to all TDP neighbors except neighbor 10.101.0.8.
Router(config)# access-list 1 permit any Router(config)# access-list 2 deny 10.101.0.8 Router(config)# tag-switching advertise-tags Router(config)# tag-switching advertise-tags for 1 to 2tag-switching atm allocation-mode
To control the mode used for handling tag binding requests on TC-ATM interfaces, use the tag-switching atm allocation-mode global configuration command. Use the no form of this command to disable this feature.
tag-switching atm allocation-mode {optimistic | conservative}
no tag-switching atm allocation-mode {optimistic | conservative}
Syntax Description
optimistic
Tag binding is returned immediately and packets are discarded until the downstream setup is complete.
conservative
Tag binding is delayed until the tag VC has been set up downstream.
Defaults
The default is conservative.
Command Modes
Global configuration
Command History
Examples
In the following example, the mode for handling binding requests is set to optimistic on a TC-ATM interface:
tag-switching atm allocation-mode optimistictag-switching atm control-vc
To configure the VPI and VCI to be used for the initial link to the Tag Switching peer device, use the tag-switching atm control-vc interface configuration command. The initial link is used to establish the TDP session and to carry non-IP traffic. To clear the interface configuration, use the no form of this command.
tag-switching atm control-vc vpi vci
no tag-switching atm control-vc vpi vci
Syntax Description
Defaults
If the subinterface has not changed to a VP tunnel, the default is 0/32. If the subinterface corresponds to VP tunnel VPI X, the default is X/32.
Command Modes
Interface configuration
Command History
Usage Guidelines
For a router interface (for example, an AIP) ATM Tag Switching can be enabled only on a tag-switch subinterface.
Note
On the Cisco LightStream 1010 ATM switch, a subinterface corresponds to a VP tunnel, so the VPI field of the control-vc must match the VPI field of the VP tunnel.
Examples
The following creates a Tag Switching subinterface on a router and selects VPI 1 and VCI 34 as the control VC:
interface atm4/0.1 tag-switchingtag-switching iptag-switching atm control-vc 1 34Related Commands
Displays the ATM TDP tag capabilities.
Displays information about one or more interfaces that have Tag Switching enabled.
tag-switching atm maxhops
To limit the maximum hop counts to a value you have specified, use the tag-switching atm maxhops global configuration command. Use the no form of this command to ignore the hop count.
tag-switching atm maxhops [number]
no tag-switching atm maxhops
Syntax Description
Defaults
The default is 254.
Command Modes
Global configuration
Command History
Usage Guidelines
When an ATM TSR receives a BIND REQUEST, it does not send a BIND back if the value in the request is equal to the maxhops value. Instead, the ATM TSR or TSR returns an error that specifies that the hop count has been reached.
When an ATM-TSR initiates a request for a tag binding, it includes a parameter specifying the maximum number of hops that the request should travel before reaching the edge of the ATM Tag Switching region. This is used to prevent forwarding loops in setting up tag paths across the ATM region.
Examples
The following example sets the hop count limit to 2:
tag-switching atm maxhops 2Related Commands
tag-switching atm vc-merge
To control whether vc-merge (multipoint-to-point) is supported for unicast tag VCs, use the tag-switching atm vc-merge global configuration command. Use the no form of this command to disable this feature.
tag-switching atm vc-merge
no tag-switching atm vc-merge
Syntax Description
This command has no arguments or keywords.
Defaults
The default is enabled if the hardware supports the ATM-VC merge capability.
Command Modes
Global configuration
Command History
Examples
The following example disables VC merge:
no tag-switching atm vc-mergeRelated Commands
tag-switching atm vpi
To configure the range of values to use in the VPI field for tag VCs, use the tag-switching atm vpi interface configuration command. To clear the interface configuration, use the no form of this command.
tag-switching atm vpi vpi [- vpi]
no tag-switching atm vpi vpi [- vpi]
Syntax Description
vpi
Virtual path identifier (low end of range).
- vpi
(Optional) Virtual path identifier (high end of range).
Defaults
The default is 1-1.
Command Modes
Interface configuration
Command History
Usage Guidelines
To configure ATM Tag Switching on a router interface (for example, an ATM Interface Processor), you must enable a Tag Switching subinterface.
Note
Use this command to select an alternate range of VPI values for ATM tag assignment on this interface. The two ends of the link negotiate a range defined by the intersection of the range configured at each end.
Examples
The following example creates a subinterface and selects a VPI range from VPI 1 to VPI 3:
interface atm4/0.1 tag-switchingtag-switching iptag-switching atm vpi 1-3Related Commands
Configures the VPI and VCI to be used for the initial link to the Tag Switching peer device.
tag-switching ip (global configuration)
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 ip
no tag-switching ip
Syntax Description
This command has no arguments or keywords.
Defaults
Tag Switching of IPv4 packets is allowed.
Command Modes
Global configuration
Command History
Usage Guidelines
Dynamic Tag Switching (that is, distribution of tags based on routing protocols) is allowed by this optional command, but it 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 command does not affect the sending of tagged packets through TSP tunnels.
For a TC-ATM interface, the no form of this command prevents the establishment of tag VCs beginning at, terminating at, or passing through the platform.
Examples
The following example prevents the distribution of dynamic tags on all interfaces:
configure terminalno tag-switching ipRelated Commands
tag-switching ip (interface configuration)
To enable Tag Switching of IPv4 packets on an interface, use the tag-switching ip interface configuration command. To disable IP Tag Switching on this interface, use the no form of this command.
tag-switching ip
no tag-switching ip
Syntax Description
This command has no arguments or keywords.
Defaults
Tag Switching of IPv4 packets is disabled on this interface.
Command Modes
Interface configuration
Command History
Usage Guidelines
The first time this command is issued on any interface, dynamic Tag Switching is enabled on the router as a whole. TDP hello messages 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 assigned with that tag.
The no form of this command causes packets routed out through this interface to be sent untagged, and outgoing TDP hello messages are no longer sent.
When the no form is issued on the only interface of a router for which Tag Switching was enabled, dynamic Tag Switching is disabled on the router as a whole.
For a TC-ATM interface, the no form of this command prevents the establishment of tag VCs beginning at, terminating at, or passing through the platform.
Examples
The following example, enables Tag Switching on the specified Ethernet interface:
configure terminalinterface e0/2tag-switching ipRelated Commands
Controls the distribution of locally assigned (incoming) tags through the TDP.
Displays information about one or more interfaces that have Tag Switching enabled.
tag-switching ip default-route
To enable the distribution of tags associated with the IP default route, use the tag-switching ip default-route global configuration command.
tag-switching ip default-route
Syntax Description
This command has no arguments or keywords.
Defaults
No distribution of IP default routes.
Command Modes
Global configuration
Command History
Usage Guidelines
Dynamic Tag Switching (that is, distribution of tags based on routing protocols) must be enabled before you can use the tag-switching ip default-route command.
The following commands enable the distribution of tags associated with the IP default route:
configure terminaltag-switching iptag-switching ip default-routeRelated Commands
tag-switching mtu
To override the per-interface maximum transmission unit (MTU), use the tag-switching mtu interface configuration command. To restore the default, use the no form of this command.
tag-switching mtu bytes
no tag-switching mtu
Syntax Description
Defaults
Minimum is 128 bytes; maximum depends on interface medium type.
Command Modes
Interface configuration
Command History
Usage Guidelines
If a tagged IP packet exceeds the MTU set for the interface, the Cisco IOS software will fragment it. All devices on a physical medium must have the same protocol MTU in order to operate.
Note
Examples
The following example sets the maximum tagged packet size for the first serial interface to 300 bytes:
interface serial 0tag-switching mtu 300tag-switching tag-range downstream
To configure the size of the tag space for downstream unicast tag allocation, use the tag-switching tag-range downstream global configuration command. Use the no form of this command to revert to the platform defaults.
tag-switching tag-range downstream min max reserved
no tag-switching tag-range downstream min max reserved
Syntax Description
Defaults
min—10
max—100000
reserved—16Command Modes
Global configuration
Command History
Examples
The following example shows how to configure the size of the tag space for downstream unicast tag allocation. In the example, min is set with the value of 10, max is set with the value of 12000, and reserved is set with the value of 16.
configure terminaltag-switching tag-range downstream 10 12000 16Related Commands
tag-switching tdp discovery
To configure the interval between transmission of TDP discovery hello messages, or the hold time for a TDP transport connection, use the tag-switching tdp discovery global configuration command.
tag-switching tdp discovery {hello | directed hello} {holdtime | interval} seconds
Syntax Description
Defaults
holdtime—15 seconds
interval—5 secondsCommand Modes
Global configuration
Command History
Examples
In the following example, the interval for which a connection stays up if no hello messages are received is set to 5 seconds:
tag-switching tdp discovery hello holdtime 5Related Commands
Displays available TDP parameters.
Enables TSP tunnel functionality on a device.
tag-switching tdp holdtime
To enable TSP tunnel functionality on a device, use the tag-switching tdp holdtime global configuration command.
tag-switching tdp holdtime seconds
Syntax Description
seconds
The time for which a TDP session is maintained in the absence of TDP messages from the session peer device.
Defaults
15 seconds
Command Modes
Global configuration
Command History
Usage Guidelines
When a TDP session is initiated, the hold time is set to the lower of the values configured at the two ends.
Examples
In the following example, the hold time of TDP sessions is configured for 30 seconds:
tag-switching tdp holdtime 30Related Commands
Displays available TDP parameters.
Configures the interval between transmission of TDP discovery hello messages.
tag-switching tsp-tunnels (global configuration)
To allow the operation of Tag-Switched Path (TSP) tunnels, use the tag-switching tsp-tunnels global configuration command. To disable the operation of TSP tunnels, use the no form of this command.
tag-switching tsp-tunnels
no tag-switching tsp-tunnels
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Global configuration
Command History
Usage Guidelines
TSP tunnel operation is allowed on the device by this optional command, but proper operation also requires that the interface-level tag-switching tsp-tunnels command be issued on the interfaces that are used by TSP tunnels. The no form of this command completely disables TSP tunnel operation on the device.
Examples
The following example allows TSP tunnel operation on a device:
configure terminalip cef distributed tag-switching tsp-tunnelsRelated Commands
ip cef
Enables CEF on the route processor card.
Displays information about the configuration and status of selected tunnels.
tag-switching tsp-tunnels (interface configuration)
To allow TSP tunnel operation over an interface, use the tag-switching tsp-tunnels interface configuration command. To disable TSP tunnel operation over an interface, use the no form of this command.
tag-switching tsp-tunnels
no tag-switching tsp-tunnels
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
TSP tunnel operation over a specific interface is allowed by this optional command. In order for TSP tunnels to operate over an interface, the tag-switching tsp-tunnels global configuration command must also be enabled. The no form of this command disables TSP tunnel operation over the specified interface.
Examples
The following example allows TSP tunnel operation over an interface:
configure terminalip cef distributedtag-switching tsp-tunnelsRelated Commands
ip cef
Enables CEF on the route processor card.
Displays information about the configuration and status of selected tunnels.
traffic-engineering filter
To specify a filter with the given number and properties, use the traffic-engineering filter command. To disable this function, use the no form of this command.
traffic-engineering filter filter-number egress ip-address mask
no traffic-engineering filter
Syntax Description
filter-number
A decimal value representing the number of the filter.
egress ip-address mask
IP address and mask for the egress port.
Command Modes
Router configuration
Command History
Usage Guidelines
You must specify that the egress is the indicated address/mask, where egress is either the destination or the BGP next hop.
Examples
In the following example, configuration is provided for the traffic engineering routing process, a traffic engineering filter, and a traffic engineering route for that filter over a TSP-encapsulated tunnel:
router traffic-engineering traffic-engineering filter 5 egress 83.0.0.1 255.255.255.255 traffic-engineering route 5 tunnel 5Related Commands
Displays information about the requested filters configured for traffic engineering.
Configures a route for a specified filter, through a specified tunnel.
traffic-engineering route
To configure a route for a specified filter, through a specified tunnel, use the traffic-engineering route command. To disable this function, use the no form of this command.
traffic-engineering route filter-number interface [preference number] [loop-prevention
{on | off}]no traffic-engineering route filter-number interface [preference number] [loop-prevention
{on | off}]Syntax Description
Defaults
preference—1
loop-prevention—onCommand Modes
Router configuration
Command History
Usage Guidelines
The traffic engineering process is used to decide if a configured traffic engineering route should be installed in the forwarding table.
The first step is to determine if the route is up. If the route is enabled, the TSP tunnel interface is up, the loop prevention check is either disabled or passed, and the traffic engineering route is up.
If multiple routes for the same filter are up, a route is selected based on administrative preference.
If loop prevention is enabled, metrics are solicited from the tunnel tail, and the loop prevention algorithm is run on the result. For a discussion of the loop prevention algorithm, see the show ip traffic-engineering metrics command.
Examples
In the following example, configuration is provided for the traffic engineering routing process, a traffic engineering filter, and a traffic engineering route for that filter through a TSP-encapsulated tunnel.
router traffic-engineeringtraffic-engineering filter 5 egress 83.0.0.1 255.255.255.255traffic-engineering route 5 tunnel 5Related Commands
Displays information about configured traffic engineering filters and routes.
Displays information about the requested filters configured for traffic engineering.
tunnel mode tag-switching
To set the encapsulation mode of the tunnel to Tag Switching, use the tunnel mode tag-switching interface configuration command. Use the no form of this command to set the tunneling encapsulation mode to the default, Generic Routing Encapsulation (GRE).
tunnel mode tag-switching
no tunnel mode tag-switching
Syntax Description
This command has no arguments or keywords.
Command Modes
Interface configuration
Command History
Usage Guidelines
A tunnel interface number must be less than or equal to 65535.
The tunnel mode tag-switching command fails if the interface number is invalid for a TSP tunnel identifier.
Examples
In the following example, the tunnel mode is set to Tag Switching:
interface tunnel 5tunnel mode tag-switchingRelated Commands
tunnel tsp-hop
To define hops in the path for the Tag Switching tunnel, use the tunnel tsp-hop interface configuration command. Use the no form of this command to remove these hops.
tunnel tsp-hop hop-number ip-address [lasthop]
no tunnel tsp-hop hop-number ip-address [lasthop]
Syntax Description
Defaults
No hops are defined.
Command Modes
Interface configuration
Command History
Usage Guidelines
The list of tunnel hops must specify a strict source route for the tunnel. In other words, the router at hop <N> must be directly connected to the router at hop <N>+1.
Examples
The following example shows the configuration of a two-hop tunnel. The first hop router/switch is 82.0.0.2, and the second and last hop is router/switch 81.0.0.2.
interface tunnel 5tunnel mode tag-switchingip unnumbered e0/1tunnel tsp-hop 1 82.0.0.2tunnel tsp-hop 2 81.0.0.2 lasthopRelated Commands
