Contents
- IS-IS Support for MTR
- Finding Feature Information
- Prerequisites for IS-IS Support for MTR
- Restrictions for IS-IS Support for MTR
- Information About IS-IS Support for MTR
- Routing Protocol Support for MTR
- Interface Configuration Support for MTR
- How to Configure IS-IS Support for MTR
- Activating an MTR Topology by Using IS-IS
- What to Do Next
- Activating an MTR Topology in Interface Configuration Mode by Using IS-IS
- Monitoring Interface and Topology IP Traffic Statistics for MTR
- Configuration Examples for IS-IS Support for MTR
- Example: Activating an MTR Topology by Using IS-IS
- Example: MTR IS-IS Topology in Interface Configuration Mode
- Additional References
- Feature Information for IS-IS Support for MTR
IS-IS Support for MTR
The IS-IS Support for MTR feature provides Intermediate System-to-Intermediate System (IS-IS) support for multiple logical topologies over a single physical network. This module describes how to configure IS-IS for Multitopology Routing (MTR) for both unicast and multicast topologies.
- Finding Feature Information
- Prerequisites for IS-IS Support for MTR
- Restrictions for IS-IS Support for MTR
- Information About IS-IS Support for MTR
- How to Configure IS-IS Support for MTR
- Configuration Examples for IS-IS Support for MTR
- Additional References
- Feature Information for IS-IS Support for MTR
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for IS-IS Support for MTR
Be familiar with the concepts in the “Routing Protocol Support for MTR” section.
Configure and activate a global topology configuration.
You must configure a multicast topology before activating the Intermediate System-to-Intermediate System (IS-IS) protocol in the multicast topology. For details, see the “MTR support for Multicast” feature module.
Activate a Multitopology Routing (MTR) topology on an IS-IS device.
Configure the MTR topology to globally configure all interfaces by using the all-interfaces address family topology configuration command, or configure the IS-IS topology in interface configuration mode to configure only IS-IS interfaces. The order in which you perform the two tasks does not matter.
Restrictions for IS-IS Support for MTR
Only the IPv4 address family (multicast and unicast) and IPv6 address family unicast are supported. For information about configuring Multitopology IS-IS for IPv6, see the IS-IS Configuration Guide.
Information About IS-IS Support for MTR
Routing Protocol Support for MTR
You must enable IP routing on the device for Multitopology Routing (MTR) to operate. MTR supports static and dynamic routing in Cisco software. You can enable dynamic routing per topology to support interdomain and intradomain routing. Route calculation and forwarding are independent for each topology. MTR support is integrated into Cisco software for the following protocols:
Border Gateway Protocol (BGP)
Enhanced Interior Gateway Routing Protocol (EIGRP)
Integrated Intermediate System-to-Intermediate System (IS-IS)
Open Shortest Path First (OSPF)
You apply the per-topology configuration in router address family configuration mode of the global routing process (router configuration mode). The address family and subaddress family are specified when the device enters address family configuration mode. You specify the topology name and topology ID by entering the topology command in address family configuration mode.
You configure each topology with a unique topology ID under the routing protocol. The topology ID is used to identify and group Network Layer Reachability Information (NLRI) for each topology in updates for a given protocol. In OSPF, EIGRP, and IS-IS, you enter the topology ID during the first configuration of the topology command for a class-specific topology. In BGP, you configure the topology ID by entering the bgp tid command under the topology configuration.
You can configure class-specific topologies with different metrics than the base topology. Interface metrics configured on the base topology can be inherited by the class-specific topology. Inheritance occurs if no explicit inheritance metric is configured in the class-specific topology.
You configure BGP support only in router configuration mode. You configure Interior Gateway Protocol (IGP) support in router configuration mode and in interface configuration mode.
By default, interfaces are not included in nonbase topologies. For routing protocol support for EIGRP, IS-IS, and OSPF, you must explicitly configure a nonbase topology on an interface. You can override the default behavior by using the all-interfaces command in address family topology configuration mode. The all-interfaces command causes the nonbase topology to be configured on all interfaces of the device that are part of the default address space or the virtual routing and forwarding (VRF) instance in which the topology is configured.
Interface Configuration Support for MTR
The configuration of a Multitopology Routing (MTR) topology in interface configuration mode allows you to enable or disable MTR on a per-interface basis. By default, a class-specific topology does not include any interfaces.
You can include or exclude individual interfaces by configuring the topology interface configuration command. You specify the address family and the topology (base or class-specific) when entering this command. The subaddress family can be specified. If no subaddress family is specified, the unicast subaddress family is used by default.
You can include globally all interfaces on a device in a topology by entering the all-interfaces command in routing topology configuration mode. Per-interface topology configuration applied with the topology command overrides global interface configuration.
The interface configuration support for MTR has these characteristics:
Per-interface routing configuration: Interior Gateway Protocol (IGP) routing and metric configurations can be applied in interface topology configuration mode. Per-interface metrics and routing behaviors can be configured for each IGP.
Open Shortest Path First (OSPF) interface topology configuration: Interface mode OSPF configurations for a class-specific topology are applied in interface topology configuration mode. In this mode, you can configure an interface cost or disable OSPF routing without removing the interface from the global topology configuration.
Enhanced Interior Gateway Routing Protocol (EIGRP) interface topology configuration: Interface mode EIGRP configurations for a class-specific topology are applied in interface topology configuration mode. In this mode, you can configure various EIGRP features.
Intermediate System-to-Intermediate System (IS-IS) interface topology configuration: Interface mode IS-IS configurations for a class-specific topology are applied in interface topology configuration mode. In this mode, you can configure an interface cost or disable IS-IS routing without removing the interface from the global topology configuration.
How to Configure IS-IS Support for MTR
Activating an MTR Topology by Using IS-IS
Note | Only Multitopology Routing (MTR) commands are shown in this task. |
1.
enable
2.
configure terminal
3.
router
isis [area-tag]
4.
net
network-entity-title
5.
metric-style wide
[transition] [level-1 |
level-2 |
level-1-2]
6.
address-family ipv4 [multicast |
unicast]
7.
topology
topology-name
tid
number
8.
end
9.
show isis neighbors detail
DETAILED STEPS
What to Do Next
If a Border Gateway Protocol (BGP) topology configuration is required, see the “BGP Support for MTR” feature module.
Activating an MTR Topology in Interface Configuration Mode by Using IS-IS
Define a topology globally before performing the per-interface topology configuration.
1.
enable
2.
configure terminal
3.
interface
type number
4.
ip address
ip-address mask [secondary]
5.
ip router isis [area-tag]
6.
topology ipv4 [multicast |
unicast] {topology-name [disable |
base]}
7.
isis topology disable
8.
topology ipv4 [multicast |
unicast] {topology-name [disable |
base]}
9.
end
DETAILED STEPS
Command or Action | Purpose | |||
---|---|---|---|---|
Step 1 |
enable
Example: Device> enable |
Enables privileged EXEC mode. | ||
Step 2 |
configure terminal
Example: Device# configure terminal |
Enters global configuration mode. | ||
Step 3 |
interface
type number
Example: Device(config)# interface Ethernet 2/0 |
Specifies the interface type and number, and enters interface configuration mode. | ||
Step 4 |
ip address
ip-address mask [secondary]
Example: Device(config-if)# ip address 192.168.7.17 255.255.255.0 |
Sets a primary or secondary IP address for an interface. | ||
Step 5 |
ip router isis [area-tag]
Example: Device(config-if)# ip router isis |
Configures an Intermediate System-to-Intermediate System (IS-IS) routing process for IP on an interface and attaches an area designator to the routing process.
| ||
Step 6 |
topology ipv4 [multicast |
unicast] {topology-name [disable |
base]}
Example: Device(config-if)# topology ipv4 DATA |
Configures a Multitopology Routing (MTR) topology instance on an interface and enters interface topology configuration mode.
| ||
Step 7 |
isis topology disable
Example: Device(config-if-topology)# isis topology disable |
(Optional) Prevents an IS-IS process from advertising the interface as part of the topology.
| ||
Step 8 |
topology ipv4 [multicast |
unicast] {topology-name [disable |
base]}
Example: Device(config-if-topology)# topology ipv4 VOICE |
Configures an MTR topology instance on an interface.
| ||
Step 9 |
end
Example: Device(config-if-topology)# end |
Exits interface topology configuration mode and returns to privileged EXEC mode. |
Monitoring Interface and Topology IP Traffic Statistics for MTR
Use any of the following commands in any order to monitor interface and topology IP traffic statistics for Multitopology Routing (MTR).
1.
enable
2.
show ip interface [type number] [topology {name |
all |
base}] [stats]
3.
show ip traffic [topology {name |
all |
base}]
4.
clear ip interface
type number [topology {name |
all |
base}] [stats]
5.
clear ip traffic [topology {name |
all |
base}]
DETAILED STEPS
Command or Action | Purpose | |
---|---|---|
Step 1 |
enable
Example: Device> enable |
Enables privileged EXEC mode. |
Step 2 |
show ip interface [type number] [topology {name |
all |
base}] [stats]
Example: Device# show ip interface FastEthernet 1/10 stats |
(Optional) Displays IP traffic statistics for all interfaces or statistics related to the specified interface.
|
Step 3 |
show ip traffic [topology {name |
all |
base}]
Example: Device# show ip traffic topology VOICE |
(Optional) Displays global IP traffic statistics (an aggregation of all the topologies when MTR is enabled) or statistics related to a particular topology. |
Step 4 |
clear ip interface
type number [topology {name |
all |
base}] [stats]
Example: Device# clear ip interface FastEthernet 1/10 topology all |
(Optional) Resets interface-level IP traffic statistics. |
Step 5 |
clear ip traffic [topology {name |
all |
base}]
Example: Device# clear ip traffic topology all |
(Optional) Resets IP traffic statistics. |
Configuration Examples for IS-IS Support for MTR
Example: Activating an MTR Topology by Using IS-IS
The following example shows how to configure both the Multitopology Routing (MTR) topologies DATA and VIDEO and Intermediate System-to-Intermediate System (IS-IS) support for MTR. The DATA and VIDEO topologies are enabled on three IS-IS neighbors in a network.
Device 1
global-address-family ipv4 topology DATA topology VOICE end interface Ethernet 0/0 ip address 192.168.128.2 255.255.255.0 ip router isis topology ipv4 DATA isis topology disable topology ipv4 VOICE end router isis net 33.3333.3333.3333.00 metric-style wide address-family ipv4 topology DATA tid 100 topology VOICE tid 200 end
Device 2
global-address-family ipv4 topology DATA topology VOICE all-interfaces forward-base maximum routes 1000 warning-only shutdown end interface Ethernet 0/0 ip address 192.168.128.1 255.255.255.0 ip router isis topology ipv4 DATA isis topology disable topology ipv4 VOICE end interface Ethernet 1/0 ip address 192.168.130.1 255.255.255.0 ip router isis topology ipv4 DATA isis topology disable topology ipv4 VOICE end router isis net 32.3232.3232.3232.00 metric-style wide address-family ipv4 topology DATA tid 100 topology VOICE tid 200 end
Device 3
global-address-family ipv4 topology DATA topology VOICE all-interfaces forward-base maximum routes 1000 warning-only shutdown end interface Ethernet 1/0 ip address 192.168.131.1 255.255.255.0 ip router isis topology ipv4 DATA isis topology disable topology ipv4 VOICE end router isis net 31.3131.3131.3131.00 metric-style wide address-family ipv4 topology DATA tid 100 topology VOICE tid 200 end
Entering the show isis neighbors detail command verifies topology translation with the IS-IS neighbor Device 1:
Device# show isis neighbors detail System Id Type Interface IP Address State Holdtime Circuit Id R1 L2 Et0/0 192.168.128.2 UP 28 R5.01 Area Address(es): 33 SNPA: aabb.cc00.1f00 State Changed: 00:07:05 LAN Priority: 64 Format: Phase V Remote TID: 100, 200 Local TID: 100, 200
Example: MTR IS-IS Topology in Interface Configuration Mode
The following example shows how to prevent the Intermediate System-to-Intermediate System (IS-IS) process from advertising interface Ethernet 1/0 as part of the DATA topology:
interface Ethernet 1/0 ip address 192.168.130.1 255.255.255.0 ip router isis topology ipv4 DATA isis topology disable topology ipv4 VOICE end
Additional References
Related Documents
Related Topic |
Document Title |
---|---|
Cisco IOS commands |
|
Multitopology Routing (MTR) commands |
|
Intermediate System-to-Intermediate System (IS-IS) commands |
|
IS-IS concepts and tasks |
IP Routing: IS-IS Configuration Guide |
Configuring a multicast topology |
“MTR Support for Multicast” feature module in the Multitopology Routing Configuration Guide |
Configure Multitopology IS-IS for IPv6 |
IP Routing: IS-IS Configuration Guide |
Technical Assistance
Description |
Link |
---|---|
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Feature Information for IS-IS Support for MTR
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Feature Name |
Releases |
Feature Information |
---|---|---|
IS-IS Support for MTR |
12.2(33)SRB Cisco IOS XE Release 2.5 |
This feature provides Intermediate System-to-Intermediate System (IS-IS) support for multiple logical topologies over a single physical network. In Cisco IOS XE Release 2.5, support was added for the Cisco ASR 1000 Series Routers. The following commands were introduced or modified: address-family ipv4, isis topology disable, show isis neighbors, topology. |