OSPF Support for Multi-VRF on CE Routers
Last Updated: May 4, 2009
The OSPF Support for Multi-VRF on CE Routers feature provides the capability to suppress provider edge (PE) checks that are needed to prevent loops when the PE is performing a mutual redistribution of packets between the OSPF and BGP protocols. When VPN routing and forwarding (VRF) is used on a router that is not a PE (that is, one that is not running BGP), the checks can be turned off to allow for correct population of the VRF routing table with routes to IP prefixes.
OSPF multi-VRF allows you to split the router into multiple virtual routers, where each router contains its own set of interfaces, routing table, and forwarding table.
Finding Feature Information
For the latest feature information and caveats, see 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 for OSPF Support for Multi-VRF on CE Routers" section.
Use Cisco Feature Navigator to find information about platform support and Cisco IOS XE software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Contents
•Information About OSPF Support for Multi-VRF on CE Routers
•How to Configure OSPF Support for Multi-VRF on CE Routers
•Configuration Example for OSPF Support for Multi-VRF on CE Routers
•Additional References
•Feature Information for OSPF Support for Multi-VRF on CE Routers
•Glossary
Information About OSPF Support for Multi-VRF on CE Routers
The OSPF Support for Multi-VRF on CE Routers feature provides the capability to suppress provider edge (PE) checks that are needed to prevent loops when the PE is performing a mutual redistribution of packets between the OSPF and BGP protocols. When VPN routing and forwarding (VRF) is used on a router that is not a PE (that is, one that is not running BGP), the checks can be turned off to allow for correct population of the VRF routing table with routes to IP prefixes.
OSPF multi-VRF allows you to split the router into multiple virtual routers, where each router contains its own set of interfaces, routing table, and forwarding table. OSPF multi-VRF gives you the ability to segment parts of your network and configure those segments to perform specific functions, yet still maintain correct routing information.
How to Configure OSPF Support for Multi-VRF on CE Routers
This section contains the following procedures:
•Configuring the Multi-VRF Capability for OSPF Routing
•Verifying the OSPF Multi-VRF Configuration
Configuring the Multi-VRF Capability for OSPF Routing
Prerequisites
CEF must be running on the network.
SUMMARY STEPS
1. enable
2. show ip ospf [process-id]
3. configure terminal
4. router ospf process-id [vrf vpn-name]
5. capability vrf-lite
DETAILED STEPS
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Step 1 |
enable
Router> enable |
Enables higher privilege levels, such as privileged EXEC mode. •Enter your password if prompted. |
Step 2 |
show ip ospf [process-id]
Router# show ip ospf 1 |
Displays the status of the router. If the display indicates that the router is connected to the VPN backbone, you can use the capability vrf-lite command to decouple the PE router from the VPN backbone. |
Step 3 |
configure terminal
Router# configure terminal |
Enters global configuration mode. |
Step 4 |
vpdn-group name
Router(config)# vpdn-group mygroup |
Creates a VPDN group. |
Step 5 |
exit
Router(config-vpdn)# exit |
Leaves the configuration mode and returns to global configuration mode. |
Step 6 |
resource-pool profile vpdn name
Router(config)# resource-pool profile vpdn company1 |
Creates a virtual private dialup network (VPDN) profile and enters VPDN profile configuration mode. |
Step 7 |
vpdn group name
Router(config-vpdn-profile)# vpdn group mygroup |
Associates a virtual private dialup network (VPDN) group with a customer or VPDN profile. |
Step 8 |
vpn {vrfvrf-name | idvpn-id}
Router(config-vpdn)# vpn vrf grc |
Specifies that the source and destination IPv4 addresses of a given virtual private dialup network (VPDN) group belong to a specified Virtual Private Network (VPN) routing and forwarding (VRF) instance. |
Step 9 |
exit
Router(config-vpdn)# exit |
Leaves the configuration mode and returns to global configuration mode. |
Step 10 |
router ospf process-id [vrf vpn-name]
Router(config)# router ospf 1 vrf grc |
Enables OSPF routing and enters router configuration mode. •The process-id argument identifies the OSPF process. •Use the vrf keyword and vpn-name argument to identify a VPN. |
Step 11 |
capability vrf-lite
Router(config-router)# capability vrf-lite |
Applies the multi-VRF capability to the OSPF process. |
Verifying the OSPF Multi-VRF Configuration
No specific debug or show commands are associated with this feature. You can verify the success of the OSPF multi-VRF configuration by using the show ip ospf [process-id] command to verify that the router is not connected to the VPN backbone.
This output from the show ip ospf process command indicates that the PE router is currently connected to the backbone.
Routing Process "ospf 12" with ID 172.16.1.1 and Domain ID 0.0.0.12
Supports only single TOS(TOS0) routes
Connected to MPLS VPN Superbackbone
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x0
Number of opaque AS LSA 0. Checksum Sum 0x0
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 0. 0 normal 0 stub 0 nssa
External flood list length 0
When the OSPF VRF process is configured with the capability vrf-lite command under the router ospf command, the "Connected to MPLS VPN Superbackbone" line will not be present in the display.
Configuration Example for OSPF Support for Multi-VRF on CE Routers
Example: Configuring the Multi-VRF Capability
This example shows a basic OSPF network with a VRF named grc configured. The capability vrf-lite command is entered to suppress the PE checks.
ip address 192.168.1.1 255.255.255.252
ip address 192.168.2.1 255.255.255.252
redistribute rip metric 1 subnets
network 192.168.1.0 0.0.0.255 area 0
address-family ipv4 vrf grc
redistribute ospf 9000 vrf grc
network network 192.168.2.0
Router# show ip route vrf grc
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
O IA 192.168.192.0/24 [110/138] via 192.168.1.13, 00:06:08, Serial2/0/0
[110/138] via 192.168.1.9, 00:06:08, Serial3/0/0
O IA 192.168.242.0/24 [110/74] via 192.168.1.13, 00:06:08, Serial2/0/0
O IA 192.168.193.0/24 [110/148] via 192.168.1.13, 00:06:08, Serial2/0/0
[110/148] via 192.168.1.9, 00:06:08, Serial3/0/0
O IA 192.168.128.0/24 [110/74] via 192.168.1.9, 00:06:08, Serial3/0/0
O IA 192.168.129.0/24 [110/84] via 192.168.1.9, 00:06:08, Serial3/0/0
O IA 192.168.130.0/24 [110/84] via 192.168.1.9, 00:06:08, Serial3/0/0
172.16.0.0/24 is subnetted, 2 subnets
O E2 172.16.9.0 [110/5] via 192.168.1.13, 00:06:08, Serial2/0/0
O E2 172.16.10.0 [110/5] via 192.168.1.13, 00:06:08, Serial2/0/0
O IA 192.168.131.0/24 [110/94] via 192.168.1.9, 00:06:20, Serial3/0/0
192.168.1.0/30 is subnetted, 4 subnets
C 192.168.1.8 is directly connected, Serial3/0/0
C 192.168.1.12 is directly connected, Serial2/0/0
O 192.168.1.0 [110/128] via 192.168.1.9, 00:06:20, Serial3/0/0
O 192.168.1.4 [110/128] via 192.168.1.13, 00:06:20, Serial2/0/0
Additional References
For additional information related to OSPF support for multi-VRF on CE routers, see the following references.
Related Documents
Standards
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No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature. |
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MIBs
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No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified by this feature. |
To locate and download MIBs for selected platforms, Cisco IOS XE software releases , and feature sets, use Cisco MIB Locator found at the following URL: http://www.cisco.com/go/mibs |
RFCs
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No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature. |
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Technical Assistance
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The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password. |
http://www.cisco.com/cisco/web/support/index.html |
Feature Information for OSPF Support for Multi-VRF on CE Routers
Table 1 lists the release history for this feature.
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which Cisco IOS XE software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Note Table 1 lists only the Cisco IOS XE software release that introduced support for a given feature in a given Cisco IOS XE software release train. Unless noted otherwise, subsequent releases of that Cisco IOS XE software release train also support that feature.
Table 1 Feature Information for OSPF Support for Multi-VRF on CE Routers
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OSPF Support for Multi-VRF on CE Routers |
Cisco IOS XE Release 2.1 |
The OSPF Support for Multi-VRF on CE Routers feature provides the capability to suppress provider edge (PE) checks that are needed to prevent loops when the PE is performing a mutual redistribution of packets between the OSPF and BGP protocols. When VPN routing and forwarding (VRF) is used on a router that is not a PE (that is, one that is not running BGP), the checks can be turned off to allow for correct population of the VRF routing table with routes to IP prefixes. The following commands are introduced or modified in the feature documented in this module: •capability vrf-lite |
Glossary
CE Router—Customer Edge router, an edge router in the C network, defined as a C router which attaches directly to a P router.
C Network—Customer (enterprise or service provider) network.
C Router—Customer router, a router in the C network.
LSA—link-state advertisement. Broadcast packet used by link-state protocols that contains information about neighbors and path costs. LSAs are used by the receiving routers to maintain their routing tables.
PE Router—Provider Edge router, an edge router in the P network, defined as a P router which attaches directly to a C router.
P Network—MPLS-capable service provider core network. P routers perform MPLS.
P Router—Provider router, a router in the P network.
SPF—shortest path first. A routing algorithm that iterates on length of path to determine a shortest-path spanning tree.
VRF—VPN Routing and Forwarding.
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Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.
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