Table Of Contents
Implementing Multiprotocol BGP for IPv6
Contents
Prerequisites for Implementing Multiprotocol BGP for IPv6
Information About Implementing Multiprotocol BGP for IPv6
Multiprotocol BGP Extensions for IPv6
Multiprotocol BGP for the IPv6 Multicast Address Family
6PE Multipath
How to Implement Multiprotocol BGP for IPv6
Configuring an IPv6 BGP Routing Process and BGP Router ID
Prerequisites
BGP Router ID for IPv6
Configuring an IPv6 Multiprotocol BGP Peer
Restrictions
Configuring an IPv6 Multiprotocol BGP Peer Using a Link-Local Address
Multiprotocol BGP Peering Using Link-Local Addresses
Restrictions
Troubleshooting Tips
Configuring an IPv6 Multiprotocol BGP Peer Group
Restrictions
What to Do Next
Advertising Routes into IPv6 Multiprotocol BGP
Restrictions
Configuring a Route Map for IPv6 Multiprotocol BGP Prefixes
Restrictions
Redistributing Prefixes into IPv6 Multiprotocol BGP
Redistribution for IPv6
Advertising IPv4 Routes Between IPv6 BGP Peers
Assigning a BGP Administrative Distance
Generating Translate Updates for IPv6 Multicast BGP
Resetting BGP Sessions
Clearing External BGP Peers
Clearing IPv6 BGP Route Dampening Information
Clearing IPv6 BGP Flap Statistics
Verifying IPv6 Multiprotocol BGP Configuration and Operation
Output Examples
Sample Output for the show bgp ipv6 Command
Sample Output for the show bgp ipv6 summary Command
Sample Output for the show bgp ipv6 dampened-paths Command
Sample Output for the debug bgp ipv6 dampening Command
Sample Output for the debug bgp ipv6 updates Command
Configuration Examples for Multiprotocol BGP for IPv6
Configuring a BGP Process, BGP Router ID, and IPv6 Multiprotocol BGP Peer: Example
Configuring an IPv6 Multiprotocol BGP Peer Using a Link-Local Address: Example
Configuring an IPv6 Multiprotocol BGP Peer Group: Example
Advertising Routes into IPv6 Multiprotocol BGP: Example
Configuring a Route Map for IPv6 Multiprotocol BGP Prefixes: Example
Redistributing Prefixes into IPv6 Multiprotocol BGP: Example
Advertising IPv4 Routes Between IPv6 Peers: Example
Where to Go Next
Additional References
Related Documents
Standards
MIBs
RFCs
Technical Assistance
Feature Information for Implementing Multiprotocol
BGP for IPv6
Implementing Multiprotocol BGP for IPv6
First Published: June 7, 2001
Last Updated: August 21, 2007
This module describes how to configure multiprotocol Border Gateway Protocol (BGP) for IPv6. BGP is an Exterior Gateway Protocol (EGP) used mainly to connect separate routing domains that contain independent routing policies (autonomous systems). Connecting to a service provider for access to the Internet is a common use for BGP. BGP can also be used within an autonomous system and this variation is referred to as internal BGP (iBGP). Multiprotocol BGP is an enhanced BGP that carries routing information for multiple network layer protocol address families, for example, IPv6 address family and for IP multicast routes. All BGP commands and routing policy capabilities can be used with multiprotocol BGP.
Finding Feature Information in This Module
Your Cisco IOS software release may not support all of the features documented in this module. To reach links to specific feature documentation in this module and to see a list of the releases in which each feature is supported, use the "Feature Information for Implementing Multiprotocol BGP for IPv6" section or the "Start Here: Cisco IOS Software Release Specifics for IPv6 Features" document.
Finding Support Information for Platforms and Cisco IOS and Catalyst OS Software Images
Use Cisco Feature Navigator to find information about platform support and Cisco IOS and Catalyst OS 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
•
Prerequisites for Implementing Multiprotocol BGP for IPv6
•Information About Implementing Multiprotocol BGP for IPv6
•How to Implement Multiprotocol BGP for IPv6
•Configuration Examples for Multiprotocol BGP for IPv6
•Where to Go Next
•Additional References
•Feature Information for Implementing Multiprotocol BGP for IPv6
Prerequisites for Implementing Multiprotocol BGP for IPv6
•This module assumes that you are familiar with IPv6 addressing and basic configuration. Refer to the Implementing IPv6 Addressing and Basic Connectivity module for more information.
•This module assumes that you are familiar with IPv4. Refer to the publications referenced in the "Related Documents" section for IPv4 configuration and command reference information.
Information About Implementing Multiprotocol BGP for IPv6
To configure multiprotocol BGP extensions for IPv6, you need to understand the following concept:
•Multiprotocol BGP Extensions for IPv6
•Multiprotocol BGP for the IPv6 Multicast Address Family
Multiprotocol BGP Extensions for IPv6
Multiprotocol BGP is the supported EGP for IPv6. Multiprotocol BGP extensions for IPv6 supports the same features and functionality as IPv4 BGP. IPv6 enhancements to multiprotocol BGP include support for an IPv6 address family and network layer reachability information (NLRI) and next hop (the next router in the path to the destination) attributes that use IPv6 addresses.
Multiprotocol BGP for the IPv6 Multicast Address Family
The multiprotocol BGP for the IPv6 multicast address family feature provides multicast BGP extensions for IPv6 and supports the same features and functionality as IPv4 BGP. IPv6 enhancements to multicast BGP include support for an IPv6 multicast address family and network layer reachability information (NLRI) and next hop (the next router in the path to the destination) attributes that use IPv6 addresses.
Multicast BGP is an enhanced BGP that allows the deployment of interdomain IPv6 multicast. Multiprotocol BGP carries routing information for multiple network layer protocol address families; for example, IPv6 address family and for IPv6 multicast routes. The IPv6 multicast address family contains routes used for RPF lookup by the IPv6 PIM protocol, and multicast BGP IPV6 provides for inter- domain transport of the same. Users must use multiprotocol BGP for IPv6 multicast when using IPv6 multicast with BGP because the unicast BGP learned routes will not be used for IPv6 multicast.
Multicast BGP functionality is provided through a separate address family context. A subsequent address family identifier (SAFI) provides information about the type of the network layer reachability information that is carried in the attribute. Multiprotocol BGP unicast uses SAFI 1 messages, and multiprotocol BGP multicast uses SAFI 2 messages. SAFI 1 messages indicate that the routes are only usable for IP unicast, but not IP multicast. Because of this functionality, BGP routes in the IPv6 unicast RIB must be ignored in the IPv6 multicast RPF lookup.
A separate BGP routing table is maintained to configure incongruent policies and topologies (for example, IPv6 unicast and multicast) by using IPv6 multicast RPF lookup. Multicast RPF lookup is very similar to the IP unicast route lookup.
No MRIB is associated with the IPv6 multicast BGP table. However, IPv6 multicast BGP operates on the unicast IPv6 RIB when needed. Multicast BGP does not insert or update routes into the IPv6 unicast RIB.
6PE Multipath
Internal and external BGP multipath for IPv6 allows the IPv6 router to load balance between several paths (for example, same neighboring autonomous system [AS] or sub-AS, or the same metric) to reach its destination. The 6PE multipath feature uses multiprotocol internal BGP (MP-iBGP) to distribute IPv6 routes over the MPLS IPv4 core network and to attach an MPLS label to each route.
When MP-iBGP multipath is enabled on the 6PE router, all labeled paths are installed in the forwarding table with MPLS information (label stack) when MPLS information is available. This functionality enables 6PE to perform load balancing.
How to Implement Multiprotocol BGP for IPv6
When configuring multiprotocol BGP extensions for IPv6, you must create the BGP routing process, configure peering relationships, and customize BGP for your particular network.
Note The following sections describe the configuration tasks for creating an IPv6 multiprotocol BGP routing process and associating peers, peer groups, and networks to the routing process. The following sections do not provide in-depth information on customizing multiprotocol BGP because the protocol functions the same in IPv6 as it does in IPv4. See the "Related Documents" section for further information on BGP and multiprotocol BGP configuration and command reference information.
The tasks in the following sections explain how to configure multiprotocol BGP extensions for IPv6. Each task in the list is identified as either required or optional:
•Configuring an IPv6 BGP Routing Process and BGP Router ID (required)
•Configuring an IPv6 Multiprotocol BGP Peer (required)
•Configuring an IPv6 Multiprotocol BGP Peer Using a Link-Local Address (optional)
•Configuring an IPv6 Multiprotocol BGP Peer Group (optional)
•Advertising Routes into IPv6 Multiprotocol BGP (required)
•Configuring a Route Map for IPv6 Multiprotocol BGP Prefixes (optional)
•Redistributing Prefixes into IPv6 Multiprotocol BGP (optional)
•Advertising IPv4 Routes Between IPv6 BGP Peers (optional)
•Assigning a BGP Administrative Distance (optional)
•Generating Translate Updates for IPv6 Multicast BGP (optional)
•Resetting BGP Sessions (optional)
•Clearing External BGP Peers (optional)
•Clearing IPv6 BGP Route Dampening Information (optional)
•Clearing IPv6 BGP Flap Statistics (optional)
•Verifying IPv6 Multiprotocol BGP Configuration and Operation (optional)
Configuring an IPv6 BGP Routing Process and BGP Router ID
This task explains how to configure an IPv6 BGP routing process and an optional BGP router ID for a BGP-speaking router.
Prerequisites
Before configuring the router to run BGP for IPv6, you must globally enable IPv6 routing using the ipv6 unicast-routing global configuration command. For details on basic IPv6 connectivity tasks, refer to the Implementing Basic Connectivity for IPv6 module.
BGP Router ID for IPv6
BGP uses a router ID to identify BGP-speaking peers. The BGP router ID is 32-bit value that is often represented by an IPv4 address. By default, the Cisco IOS software sets the router ID to the IPv4 address of a loopback interface on the router. If no loopback interface is configured on the router, then the software chooses the highest IPv4 address configured to a physical interface on the router to represent the BGP router ID. When configuring BGP on a router that is enabled only for IPv6 (the router does not have an IPv4 address), you must manually configure the BGP router ID for the router. The BGP router ID, which is represented as a 32-bit value using an IPv4 address syntax, must be unique to the BGP peers of the router.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. no bgp default ipv4-unicast
5. bgp router-id ip-address
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
•Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
router bgp as-number
Example:
Router(config)# router bgp 65000
|
Configures a BGP routing process, and enters router configuration mode for the specified routing process.
|
Step 4
|
no bgp default ipv4-unicast
Example:
Router(config-router)# no bgp default
ipv4-unicast
|
Disables the IPv4 unicast address family for the BGP routing process specified in the previous step.
Note Routing information for the IPv4 unicast address family is advertised by default for each BGP routing session configured with the neighbor remote-as router configuration command unless you configure the no bgp default ipv4-unicast router configuration command before configuring the neighbor remote-as command.
|
Step 5
|
bgp router-id ip-address
Example:
Router(config-router)# bgp router-id
192.168.99.70
|
(Optional) Configures a fixed 32-bit router ID as the identifier of the local router running BGP.
Note Configuring a router ID using the bgp router-id command resets all active BGP peering sessions.
|
Configuring an IPv6 Multiprotocol BGP Peer
This task explains how to configure IPv6 multiprotocol BGP between two IPv6 routers (peers).
Restrictions
By default, neighbors that are defined using the neighbor remote-as command in router configuration mode exchange only IPv4 unicast address prefixes. To exchange other address prefix types, such as IPv6 prefixes, neighbors must also be activated using the neighbor activate command in address family configuration mode for the other prefix types, as shown for IPv6 prefixes.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. neighbor {ip-address | ipv6-address | peer-group-name} remote-as as-number
5. address-family ipv6 [unicast | multicast]
6. neighbor {ip-address | peer-group-name | ipv6-address} activate
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
•Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
router bgp as-number
Example:
Router(config)# router bgp 65000
|
Enters router configuration mode for the specified routing process.
|
Step 4
|
neighbor {ip-address | ipv6-address |
peer-group-name} remote-as as-number
Example:
Router(config-router)# neighbor
2001:0DB8:0:CC00::1 remote-as 64600
|
Adds the IPv6 address of the neighbor in the specified autonomous system to the IPv6 multiprotocol BGP neighbor table of the local router.
•The ipv6-address argument in the neighbor remote-as command must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.
|
Step 5
|
address-family ipv6 [unicast | multicast]
Example:
Router(config-router)# address-family ipv6
|
Specifies the IPv6 address family and enters address family configuration mode.
•The unicast keyword specifies the IPv6 unicast address family. By default, the router is placed in configuration mode for the IPv6 unicast address family if the unicast keyword is not specified with the address-family ipv6 command.
•The multicast keyword specifies IPv6 multicast address prefixes.
|
Step 6
|
neighbor {ip-address | peer-group-name |
ipv6-address} activate
Example:
Router(config-router-af)# neighbor
2001:0DB8:0:CC00::1 activate
|
Enables the neighbor to exchange prefixes for the IPv6 address family with the local router.
|
Configuring an IPv6 Multiprotocol BGP Peer Using a Link-Local Address
This task explains how to configure IPv6 multiprotocol BGP between two peers using link-local addresses.
Multiprotocol BGP Peering Using Link-Local Addresses
Configuring IPv6 multiprotocol BGP between two IPv6 routers (peers) using link-local addresses requires that the interface for the neighbor be identified by using the update-source router configuration command and that a route map be configured to set an IPv6 global next hop.
Restrictions
•By default, neighbors that are defined using the neighbor remote-as command in router configuration mode exchange only IPv4 unicast address prefixes. To exchange other address prefix types, such as IPv6 prefixes, neighbors must also be activated using the neighbor activate command in address family configuration mode for the other prefix types, as shown for IPv6 prefixes.
•By default, route maps that are applied in router configuration mode using the neighbor route-map command are applied to only IPv4 unicast address prefixes. Route maps for other address families must be applied in address family configuration mode using the neighbor route-map command, as shown for the IPv6 address family. The route maps are applied either as the inbound or outbound routing policy for neighbors under the specified address family. Configuring separate route maps under each address family type simplifies managing complicated or different policies for each address family.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp autonomous-system-number
4. neighbor {ip-address | ipv6-address | peer-group-name} remote-as as-number
5. neighbor {ip-address | ipv6-address | peer-group-name} update-source interface-type interface-number
6. address-family ipv6 [unicast | multicast]
7. neighbor {ip-address | peer-group-name | ipv6-address} activate
8. neighbor {ip-address | peer-group-name | ipv6-address} route-map map-name {in | out}
9. exit
10. Repeat Step 9.
11. route-map map-tag [permit | deny] [sequence-number]
12. match ipv6 address {prefix-list prefix-list-name | access-list-name}
13. set ipv6 next-hop ipv6-address [link-local-address] [peer-address]
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
•Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
router bgp autonomous-system-number
Example:
Router(config)# router bgp 65000
|
Enters router configuration mode for the specified routing process.
|
Step 4
|
neighbor {ip-address | ipv6-address |
peer-group-name} remote-as as-number
Example:
Router(config-router)# neighbor
FE80::XXXX:BFF:FE0E:A471 remote-as 64600
|
Adds the link-local IPv6 address of the neighbor in the specified remote autonomous system to the IPv6 multiprotocol BGP neighbor table of the local router.
•The ipv6-address argument in the neighbor remote-as command must be a link-local IPv6 address in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.
|
Step 5
|
neighbor {ip-address | ipv6-address |
peer-group-name} update-source interface-type
interface-number
Example:
Router(config-router)# neighbor
FE80::XXXX:BFF:FE0E:A471 update-source
fastethernet0
|
Specifies the link-local address over which the peering is to occur.
•If there are multiple connections to the neighbor and you do not specify the neighbor interface by using the interface-type and interface-number arguments in the neighbor update-source command, a TCP connection cannot be established with the neighbor using link-local addresses.
|
Step 6
|
address-family ipv6 [unicast | multicast]
Example:
Router(config-router)# address-family ipv6
|
Specifies the IPv6 address family, and enters address family configuration mode.
•The unicast keyword specifies the IPv6 unicast address family. By default, the router is placed in configuration mode for the IPv6 unicast address family if the unicast keyword is not specified with the address-family ipv6 command.
•The multicast keyword specifies IPv6 multicast address prefixes.
|
Step 7
|
neighbor {ip-address | peer-group-name |
ipv6-address} activate
Example:
Router(config-router-af)# neighbor
FE80::XXXX:BFF:FE0E:A471 activate
|
Enables the neighbor to exchange prefixes for the IPv6 address family with the local router using the specified link-local addresses.
|
Step 8
|
neighbor {ip-address | peer-group-name |
ipv6-address} route-map map-name {in | out}
Example:
Router(config-router-af)# neighbor
FE80::XXXX:BFF:FE0E:A471 route-map nh6 out
|
Applies a route map to incoming or outgoing routes.
|
Step 9
|
exit
Example:
Router(config-router-af)# exit
|
Exits address family configuration mode, and returns the router to router configuration mode.
|
Step 10
|
Repeat Step 9.
Example:
Router(config-router)# exit
|
Exits router configuration mode, and returns the router to global configuration mode.
|
Step 11
|
route-map map-tag [permit | deny]
[sequence-number]
Example:
Router(config)# route-map nh6 permit 10
|
Defines a route map and enters route-map configuration mode.
•Follow this step with a match command.
|
Step 12
|
match ipv6 address {prefix-list
prefix-list-name | access-list-name}
Example:
Router(config-route-map)# match ipv6 address
prefix-list cisco
|
Distributes any routes that have a destination IPv6 network number address permitted by a prefix list, or performs policy routing on packets.
•Follow this step with a set command.
|
Step 13
|
set ipv6 next-hop ipv6-address
[link-local-address] [peer-address]
Example:
Router(config-route-map)# set ipv6 next-hop
2001:0DB8::1
|
Overrides the next hop advertised to the peer for IPv6 packets that pass a match clause of a route map for policy routing.
•The ipv6-address argument specifies the IPv6 global address of the next hop. It need not be an adjacent router.
•The link-local-address argument specifies the IPv6 link-local address of the next hop. It must be an adjacent router.
Note The route map sets the IPv6 next-hop addresses (global and link-local) in BGP updates. If the route map is not configured, the next-hop address in the BGP updates defaults to the unspecified IPv6 address (::), which is rejected by the peer.
If you specify only the global IPv6 next-hop address (the ipv6-address argument) with the set ipv6 next-hop command after specifying the neighbor interface (the interface-type argument) with the neighbor update-source command in Step 5, the link-local address of the interface specified with the interface-type argument is included as the next-hop in the BGP updates. Therefore, only one route map that sets the global IPv6 next-hop address in BGP updates is required for multiple BGP peers that use link-local addresses.
|
Troubleshooting Tips
Peering not established by this task may be due to a missing route map set ipv6 next-hop command. Use the debug bgp ipv6 update command to display debugging information on the updates to help determine the state of the peering.
Configuring an IPv6 Multiprotocol BGP Peer Group
This task explains how to configure an IPv6 peer group to perform multiprotocol BGP routing.
Restrictions
•By default, neighbors that are defined using the neighbor remote-as command in router configuration mode exchange only IPv4 unicast address prefixes. To exchange other address prefix types, such as IPv6 prefixes, neighbors must also be activated using the neighbor activate command in address family configuration mode for the other prefix types, as shown for IPv6 prefixes.
•By default, peer groups that are defined in router configuration mode using the neighbor peer-group command exchange only IPv4 unicast address prefixes. To exchange other address prefix types, such as IPv6 prefixes, you must activate peer groups using the neighbor activate command in address family configuration mode for the other prefix types, as shown for IPv6 prefixes.
•Members of a peer group automatically inherit the address prefix configuration of the peer group.
•IPv4 active neighbors cannot exist in the same peer group as active IPv6 neighbors. Create separate peer groups for IPv4 peers and IPv6 peers.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. neighbor peer-group-name peer-group
5. neighbor {ip-address | ipv6-address | peer-group-name} remote-as as-number
6. address-family ipv6 [unicast | multicast]
7. neighbor {ip-address | peer-group-name | ipv6-address} activate
8. neighbor {ip-address | ipv6-address} send-label
9. neighbor {ip-address | ipv6-address} peer-group peer-group-name
10. exit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
•Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
router bgp as-number
Example:
Router(config)# router bgp 65000
|
Enters router configuration mode for the specified BGP routing process.
|
Step 4
|
neighbor peer-group-name peer-group
Example:
Router(config-router)# neighbor group1
peer-group
|
Creates a multiprotocol BGP peer group.
|
Step 5
|
neighbor {ip-address | ipv6-address |
peer-group-name} remote-as as-number
Example:
Router(config-router)# neighbor
2001:0DB8:0:CC00::1 remote-as 64600
|
Adds the IPv6 address of the neighbor in the specified autonomous system to the IPv6 multiprotocol BGP neighbor table of the local router.
•The ipv6-address argument in the neighbor remote-as command must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.
|
Step 6
|
address-family ipv6 [unicast | multicast]
Example:
Router(config-router)# address-family ipv6
unicast
|
Specifies the IPv6 address family, and enters address family configuration mode.
•The unicast keyword specifies the IPv6 unicast address family. By default, the router is placed in configuration mode for the IPv6 unicast address family if the unicast keyword is not specified with the address-family ipv6 command.
•The multicast keyword specifies IPv6 multicast address prefixes.
|
Step 7
|
neighbor {ip-address | peer-group-name |
ipv6-address} activate
Example:
Router(config-router-af)# neighbor
2001:0DB8:0:CC00::1 activate
|
Enables the neighbor to exchange prefixes for the specified family type with the neighbor and the local router.
•To avoid extra configuration steps for each neighbor, use the neighbor activate command with the peer-group-name argument as an alternative in this step.
|
Step 8
|
neighbor {ip-address | ipv6-address} send-label
Example:
Router(config-router-af)# neighbor
192.168.99.70 send-label
|
Advertises the capability of the router to send MPLS labels with BGP routes.
•In IPv6 address family configuration mode, this command enables binding and advertisement of aggregate labels when advertising IPv6 prefixes in BGP.
|
Step 9
|
neighbor {ip-address | ipv6-address} peer-group
peer-group-name
Example:
Router(config-router-af)# neighbor
2001:0DB8:0:CC00::1 peer-group group1
|
Assigns the IPv6 address of a BGP neighbor to a peer group.
|
Step 10
|
exit
Example:
Router(config-router-af)# exit
|
Exits address family configuration mode, and returns the router to router configuration mode.
•Repeat this step to exit router configuration mode and return the router to global configuration mode.
|
What to Do Next
Refer to the section "Configure BGP Peer Groups" of the "Configuring BGP" chapter in Cisco IOS IP Configuration Guide, Release 12.4, for more information on assigning options to peer groups and making a BGP or multiprotocol BGP neighbor a member of a peer group.
Advertising Routes into IPv6 Multiprotocol BGP
This task explains how to advertise (inject) a prefix into IPv6 multiprotocol BGP.
Restrictions
By default, networks that are defined in router configuration mode using the network command are injected into the IPv4 unicast database. To inject a network into another database, such as the IPv6 BGP database, you must define the network using the network command in address family configuration mode for the other database, as shown for the IPv6 BGP database.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. address-family ipv6 [unicast | multicast]
5. network {network-number [mask network-mask] | nsap-prefix} [route-map map-tag]
6. exit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
•Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
router bgp as-number
Example:
Router(config)# router bgp 65000
|
Enters router configuration mode for the specified BGP routing process.
|
Step 4
|
address-family ipv6 [unicast | multicast]
Example:
Router(config-router)# address-family ipv6
unicast
|
Specifies the IPv6 address family, and enters address family configuration mode.
•The unicast keyword specifies the IPv6 unicast address family. By default, the router is placed in configuration mode for the IPv6 unicast address family if the unicast keyword is not specified with the address-family ipv6 command.
•The multicast keyword specifies IPv6 multicast address prefixes.
|
Step 5
|
network {network-number [mask network-mask] |
nsap-prefix} [route-map map-tag]
Example:
Router(config-router-af)# network
2001:0DB8::/24
|
Advertises (injects) the specified prefix into the IPv6 BGP database. (The routes must first be found in the IPv6 unicast routing table.)
•Specifically, the prefix is injected into the database for the address family specified in the previous step.
•Routes are tagged from the specified prefix as "local origin."
•The ipv6-prefix argument in the network command must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.
•The prefix-length argument is a decimal value that indicates how many of the high-order contiguous bits of the address comprise the prefix (the network portion of the address). A slash mark must precede the decimal value.
|
Step 6
|
exit
Example:
Router(config-router-af)# exit
|
Exits address family configuration mode, and returns the router to router configuration mode.
•Repeat this step to exit router configuration mode and return the router to global configuration mode.
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Configuring a Route Map for IPv6 Multiprotocol BGP Prefixes
This task explains how to configure a route map for IPv6 multiprotocol BGP prefixes.
Restrictions
•By default, neighbors that are defined using the neighbor remote-as command in router configuration mode exchange only IPv4 unicast address prefixes. To exchange other address prefix types, such as IPv6 prefixes, neighbors must also be activated using the neighbor activate command in address family configuration mode for the other prefix types, as shown for IPv6 prefixes.
•By default, route maps that are applied in router configuration mode using the neighbor route-map command are applied to only IPv4 unicast address prefixes. Route maps for other address families must be applied in address family configuration mode using the neighbor route-map command, as shown for the IPv6 address family. The route maps are applied either as the inbound or outbound routing policy for neighbors under the specified address family. Configuring separate route maps under each address family type simplifies managing complicated or different policies for each address family.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. neighbor {ip-address | ipv6-address | peer-group-name} remote-as as-number
5. address-family ipv6 [unicast | multicast]
6. neighbor {ip-address | peer-group-name | ipv6-address} activate
7. neighbor {ip-address | peer-group-name | ipv6-address} route-map map-name {in | out}
8. exit
9. Repeat Step 8.
10. route-map map-tag [permit | deny] [sequence-number]
11. match ipv6 address {prefix-list prefix-list-name | access-list-name}
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
•Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
router bgp as-number
Example:
Router(config)# router bgp 65000
|
Enters router configuration mode for the specified routing process.
|
Step 4
|
neighbor {ip-address | ipv6-address |
peer-group-name} remote-as as-number
Example:
Router(config-router)# neighbor
2001:0DB8:0:cc00::1 remote-as 64600
|
Adds the link-local IPv6 address of the neighbor in the specified remote autonomous system to the IPv6 multiprotocol BGP neighbor table of the local router.
•The ipv6-address argument in the neighbor remote-as command must be a link-local IPv6 address in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.
|
Step 5
|
address-family ipv6 [unicast | multicast]
Example:
Router(config-router)# address-family ipv6
|
Specifies the IPv6 address family, and enters address family configuration mode.
•The unicast keyword specifies the IPv6 unicast address family. By default, the router is placed in configuration mode for the IPv6 unicast address family if the unicast keyword is not specified with the address-family ipv6 command.
•The multicast keyword specifies IPv6 multicast address prefixes.
|
Step 6
|
neighbor {ip-address | peer-group-name |
ipv6-address} activate
Example:
Router(config-router-af)# neighbor
2001:0DB8:0:cc00::1 activate
|
Enables the neighbor to exchange prefixes for the IPv6 address family with the local router using the specified link-local addresses.
|
Step 7
|
neighbor {ip-address | peer-group-name |
ipv6-address} route-map map-name {in | out}
Example:
Router(config-router-af)# neighbor
2001:0DB8:0:cc00::1 route-map rtp in
|
Applies a route map to incoming or outgoing routes.
•Changes to the route map will not take effect for existing peers until the peering is reset or a soft reset is performed. Using the clear bgp ipv6 command with the soft and in keywords will perform a soft reset.
|
Step 8
|
exit
Example:
Router(config-router-af)# exit
|
Exits address family configuration mode, and returns the router to router configuration mode.
|
Step 9
|
Repeat Step 8.
Example:
Router(config-router)# exit
|
Exits router configuration mode, and returns the router to global configuration mode.
|
Step 10
|
route-map map-tag [permit | deny]
[sequence-number]
Example:
Router(config)# route-map rtp permit 10
|
Defines a route map and enters route-map configuration mode.
•Follow this step with a match command.
|
Step 11
|
match ipv6 address {prefix-list
prefix-list-name | access-list-name}
Example:
Router(config-route-map)# match ipv6 address
prefix-list cisco
|
Distributes any routes that have a destination IPv6 network number address permitted by a prefix list, or performs policy routing on packets.
|
Redistributing Prefixes into IPv6 Multiprotocol BGP
This task explains how to redistribute (inject) prefixes from another routing protocol into IPv6 multiprotocol BGP.
Redistribution for IPv6
Redistribution is the process of injecting prefixes from one routing protocol into another routing protocol. This task explains how to inject prefixes from a routing protocol into IPv6 multiprotocol BGP. Specifically, prefixes that are redistributed into IPv6 multiprotocol BGP using the redistribute router configuration command are injected into the IPv6 unicast database.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. address-family ipv6 [unicast | multicast]
5. redistribute bgp [process-id] [[metric metric-value] [route-map map-name]] [source-protocol-options]
6. exit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
•Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
router bgp as-number
Example:
Router(config)# router bgp 65000
|
Enters router configuration mode for the specified BGP routing process.
|
Step 4
|
address-family ipv6 [unicast | multicast]
Exam |
