BGP per Neighbor SoO Configuration
First Published: November 17, 2006
Last Updated: November 25, 2009
The BGP per Neighbor SoO Configuration feature simplifies the configuration of the site-of-origin (SoO) value. In Cisco IOS Release 12.4(9)T, 12.2(33)SRA, 12.2(31)SB2, and previous releases, the SoO value is configured using an inbound route map that sets the SoO value during the update process. Per neighbor SoO configuration introduces two new commands that can be configured in submodes under router configuration mode to set the SoO value. In Cisco IOS Release 12.4(24)T, support was added for 4-byte autonomous system numbers in asdot format only.
Finding Feature Information
Your software release may not support all the features documented in this module. 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 BGP per Neighbor SoO Configuration" section.
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Contents
•Prerequisites for BGP per Neighbor SoO Configuration
•Restrictions for BGP per Neighbor SoO Configuration
•Information About Configuring BGP per Neighbor SoO
•How to Configure BGP per Neighbor SoO
•Configuration Examples for BGP per Neighbor SoO Configuration
•Where to Go Next
•Additional References
•Feature Information for BGP per Neighbor SoO Configuration
•Feature Information for BGP per Neighbor SoO Configuration
Prerequisites for BGP per Neighbor SoO Configuration
This feature assumes that a Border Gateway Protocol (BGP) network is configured and that Cisco Express Forwarding (CEF) is enabled in your network.
Restrictions for BGP per Neighbor SoO Configuration
A BGP neighbor or peer policy template-based SoO configuration takes precedence over the SoO value configured in an inbound route map.
Information About Configuring BGP per Neighbor SoO
Before configuring SoO values for BGP neighbors, you should understand the following concepts:
•Site of Origin BGP Community Attribute
•Route Distinguisher
•BGP Support for 4-Byte Autonomous System Numbers
•BGP per Neighbor Site of Origin Configuration
•Benefits of BGP per Neighbor Site of Origin
Site of Origin BGP Community Attribute
The site-of-origin (SoO) extended community is a BGP extended community attribute that is used to identify routes that have originated from a site so that the readvertisement of that prefix back to the source site can be prevented. The SoO extended community uniquely identifies the site from which a router has learned a route. BGP can use the SoO value associated with a route to prevent routing loops.
Route Distinguisher
A route distinguisher (RD) creates routing and forwarding tables and specifies the default route distinguisher for a VPN. The RD is added to the beginning of an IPv4 prefix to change it into a globally unique VPN-IPv4 prefix. An RD can be composed in one of two ways: with an autonomous system number and an arbitrary number or with an IP address and an arbitrary number.
You can enter an RD in either of these formats:
•Enter a 16-bit autonomous system number, a colon, and a 32-bit number. For example:
45000:3
•Enter a 32-bit IP address, a colon, and a 16-bit number. For example:
192.168.10.15:1
BGP Support for 4-Byte Autonomous System Numbers
In Cisco IOS Release 12.4(24)T, support was added for 4-byte autonomous system numbers as described in RFC 5396, Textual Representation of Autonomous System (AS) Numbers. In Cisco IOS Release 12.4(24)T, the Cisco implementation of 4-byte autonomous system numbers uses asdot notation—1.2 for example—as the only configuration format, regular expression match, and output display, with no asplain support.
In Cisco IOS Release 12.2(33)SRE, 12.2(33)XNE, and later releases, BGP support for 4-octet (4-byte) autonomous system numbers using the asplain format as the default format was introduced. The default asplain format uses decimal value numbers such as 65536, but you can configure 4-byte autonomous system numbers in both the asplain and asdot format. If you want to change the default show command output to display 4-byte autonomous system numbers in the asdot format, use the bgp asnotation dot command under router configuration mode.
For configuration examples involving 4-byte autonomous system numbers, see the "Configuring a per Neighbor SoO Value with a 4-Byte Autonomous System Number Using a BGP Peer Policy Template: Example" section or the "Configuring a per Neighbor SoO Value Using a BGP neighbor Command and 4-Byte Autonomous System Numbers: Example" section.
For more details about the Cisco implementation of BGP autonomous system number formats, see the the "Cisco BGP Overview" module.
BGP per Neighbor Site of Origin Configuration
There are three ways to configure an SoO value for a BGP neighbor:
•BGP peer policy template—A peer policy template is created, and an SoO value is configured as part of the peer policy. Under address family IPv4 VRF, a neighbor is identified and is configured to inherit the peer policy that contains the SoO value.
•BGP neighbor command—Under address family IPv4 VRF, a neighbor is identified, and an SoO value is configured for the neighbor.
•BGP peer group—Under address family IPv4 VRF, a BGP peer group is configured, an SoO value is configured for the peer group, a neighbor is identified, and the neighbor is configured as a member of the peer group.
The configuration of SoO values for BGP neighbors is performed on a provider edge (PE) router, which is the VPN entry point. When SoO is enabled, the PE router forwards prefixes to the customer premises equipment (CPE) only when the SoO tag of the prefix does not match the SoO tag configured for the CPE. For example, in Figure 1, an SoO tag is set as 65000:1 for the customer site that includes routers CPE1 and CPE2 with an autonomous system number of 65000. When CPE1 sends prefixes to PE1, PE1 tags the prefixes with 65000:1, which is the SoO tag for CPE1 and CPE2. When PE1 sends the tagged prefixes to PE2, PE2 performs a match against the SoO tag from CPE2. Any prefixes with the tag value of 65000:1 are not sent to CPE2 because the SoO tag matches the SoO tag of CPE2, and a routing loop is avoided.
Figure 1 Network Diagram for SoO Example
Benefits of BGP per Neighbor Site of Origin
In releases prior to Cisco IOS Release 12.4(11)T, 12.2(33)SRB, and 12.2(33)SB, the SoO extended community attribute is configured using an inbound route map that sets the SoO value during the update process. The introduction of two new commands configured in submodes under router configuration mode simplifies the SoO value configuration.
How to Configure BGP per Neighbor SoO
To configure an SoO value for a BGP neighbor, you must perform the first task in the following list and one of the next three tasks. The last three tasks are mutually exclusive; you need perform only one of them.
•Verifying CEF and Configuring VRF Instances
•Configuring a per Neighbor SoO Value Using a BGP Peer Policy Template
•Configuring a per Neighbor SoO Value Using a BGP neighbor Command
•Configuring a per Neighbor SoO Value Using a BGP Peer Group
Verifying CEF and Configuring VRF Instances
Perform this task on both of the PE routers in Figure 1 to configure Virtual Routing and Forwarding (VRF) instances to be used with the per-VRF assignment tasks. In this task, After checking that CEF is enabled, a VRF instance named SOO_VRF is configured. To make the VRF functional, a route distinguisher is created, and the VRF is associated with an interface. When the route distinguisher is created, the routing and forwarding tables are created for the VRF instance named SOO_VRF. After associating the VRF with an interface, the interface is configured with an IP address.
SUMMARY STEPS
1. enable
2. show ip cef
3. configure terminal
4. ip vrf vrf-name
5. rd route-distinguisher
6. route-target {import | both} route-target-ext-community
7. route-target {export | both} route-target-ext-community
8. exit
9. interface type number
10. ip vrf forwarding vrf-name [downstream vrf-name2]
11. ip address ip-address mask [secondary]
12. end
13. show ip vrf [brief | detail | interfaces | id] [vrf-name] [output-modifiers]
DETAILED STEPS
|
|
|
Step 1 |
enable
Router> enable |
Enables privileged EXEC mode. •Enter your password if prompted. |
Step 2 |
show ip cef
Router# show ip cef |
Verifies that CEF is enabled. •CEF is enabled by default in most Cisco IOS Releases. •If CEF is not enabled, enter the ip cef command in global configuration mode. Some platforms require additional keywords with this command. For more details, see the Cisco IOS IP Switching Command Reference. |
Step 3 |
configure terminal
Router# configure terminal |
Enters global configuration mode. |
Step 4 |
ip vrf vrf-name
Router(config)# ip vrf SOO_VRF |
Defines a VRF instance and enters VRF configuration mode. |
Step 5 |
rd route-distinguisher
Router(config-vrf)# rd 1:1 |
Creates routing and forwarding tables for a VRF and specifies the default RD for a VPN. •Use the route-distinguisher argument to specify the default RD for a VPN. There are two formats that you can use to specify an RD: –A 16-bit autonomous system number, a colon, and a 32-bit number, for example: 65000:3 –A 32-bit IP address, a colon, and a 16-bit number, for example: 192.168.1.2:51 •In this example, the RD uses an autonomous system number with the number 1 after the colon. |
Step 6 |
route-target {export | both} route-target-ext-community
Router(config-vrf)# route-target export 1:1 |
Creates a route-target extended community for a VRF. •Use the export keyword to export routing information to the target VPN extended community. •Use the both keyword to both import routing information from, and export routing information to, the target VPN extended community. •Use the route-target-ext-community argument to specify the VPN extended community. Note Only the syntax applicable to this step is displayed. For a different use of this syntax, see Step 7. |
Step 7 |
route-target {import | both} route-target-ext-community
Router(config-vrf)# route-target import 1:1 |
Creates a route-target extended community for a VRF. •Use the import keyword to import routing information from the target VPN extended community. •Use the both keyword to both import routing information from, and export routing information to, the target VPN extended community. •Use the route-target-ext-community argument to specify the VPN extended community. |
Step 8 |
exit
Router(config-vrf)# exit |
Exits VRF configuration mode and returns to global configuration mode. |
Step 9 |
interface type number
Router(config)# interface Ethernet 1/0 |
Configures an interface type and enters interface configuration mode. •In this example, Ethernet interface 1/0 is configured. |
Step 10 |
ip vrf forwarding vrf-name [downstream vrf-name2]
Router(config-if)# ip vrf forwarding SOO_VRF |
Associates a VRF with an interface or subinterface. •In this example, the VRF named SOO_VRF is associated with Ethernet interface 1/0. Note Executing this command on an interface removes the IP address, so the IP address should be reconfigured. |
Step 11 |
ip address ip-address mask [secondary]
Router(config-if)# ip address 192.168.1.2 255.255.255.0 |
Configures an IP address. •In this example, Ethernet interface 1/0 is configured with an IP address of 192.168.1.2. |
Step 12 |
end
Router(config-if)# end |
Exits interface configuration mode and returns to privileged EXEC mode. |
Step 13 |
show ip vrf [brief | detail | interfaces | id] [vrf-name] [output-modifiers]
Router# show ip vrf |
Displays the configured VRFs. •Use this command to verify the configuration of this task. |
Examples
The following output of the show ip vrf command displays the VRF named SOO_VRF configured in this task.
Name Default RD Interfaces
Configuring a per Neighbor SoO Value Using a BGP Peer Policy Template
Perform this task on router PE1 in Figure 1 to configure an SoO value for a BGP neighbor at the router CPE1 in Figure 1 using a peer policy template. In this task, a peer policy template is created, and the SoO value is configured for the peer policy. Under address family IPv4 VRF, a neighbor is identified and is configured to inherit the peer policy that contains the SoO value.
For a configuration example involving 4-byte autonomous system numbers, see the "Configuring a per Neighbor SoO Value with a 4-Byte Autonomous System Number Using a BGP Peer Policy Template: Example" section.
Note If a BGP peer inherits from several peer policy templates that specify different SoO values, the SoO value in the last template applied takes precedence and is applied to the peer. However, direct configuration of the SoO value on the BGP neighbor overrides any inherited template configurations of the SoO value.
BGP Peer Policy Templates
Peer policy templates are used to configure BGP policy commands that are configured for neighbors that belong to specific address families. Peer policy templates are configured once and then applied to many neighbors through the direct application of a peer policy template or through inheritance from peer policy templates. The configuration of peer policy templates simplifies the configuration of BGP policy commands that are applied to all neighbors within an autonomous system.
Peer policy templates support inheritance. A directly applied peer policy template can directly or indirectly inherit configurations from up to seven peer policy templates. So, a total of eight peer policy templates can be applied to a neighbor or neighbor group.
The configuration of peer policy templates simplifies and improves the flexibility of BGP configuration. A specific policy can be configured once and referenced many times. Because a peer policy supports up to eight levels of inheritance, very specific and very complex BGP policies can be created.
For more details about BGP peer policy templates, see the "Configuring a Basic BGP Network" module.
Prerequisites
This task assumes that the task described in the "Verifying CEF and Configuring VRF Instances" section has been performed.
Restrictions
A BGP peer cannot inherit from a peer policy or session template and be configured as a peer group member at the same. BGP templates and BGP peer groups are mutually exclusive.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp autonomous-system-number
4. template peer-policy policy-template-name
5. soo extended-community-value
6. exit-peer-policy
7. address-family ipv4 [unicast | multicast | vrf vrf-name]
8. neighbor ip-address remote-as autonomous-system-number
9. neighbor ip-address activate
10. neighbor ip-address inherit peer-policy policy-template-name
11. end
DETAILED STEPS
|
|
|
Step 1 |
enable
Router> enable |
Enables privileged EXEC mode. •Enter your password if prompted. |
Step 2 |
configure terminal
Router# configure terminal |
Enters global configuration mode. |
Step 3 |
router bgp autonomous-system-number
Router(config)# router bgp 50000 |
Enters router configuration mode for the specified routing process. |
Step 4 |
template peer-policy policy-template-name
Router(config-router)# template peer-policy SOO_POLICY |
Creates a peer policy template and enters policy-template configuration mode. |
Step 5 |
soo extended-community-value
Router(config-router-ptmp)# soo 65000:1 |
Sets the SoO value for a BGP peer policy template. •Use the extended-community-value argument to specify the VPN extended community value. The value takes one of the following formats: –A 16-bit autonomous system number, a colon, and a 32-bit number, for example: 45000:3 –A 32-bit IP address, a colon, and a 16-bit number, for example: 192.168.10.2:51 •In this example, the SoO value is set at 65000:1. |
Step 6 |
exit-peer-policy
Router(config-router-pmtp)# exit-peer-policy |
Exits policy-template configuration mode and returns to router configuration mode. |
Step 7 |
address-family ipv4 [unicast | multicast | vrf vrf-name]
Router(config-router)# address-family ipv4 vrf SOO_VRF |
Specifies the IPv4 address family and enters address family configuration mode. •Use the unicast keyword to specify the IPv4 unicast address family. By default, the router is placed in configuration mode for the IPv4 unicast address family if the unicast keyword is not specified with the address-family ipv4 command. •Use the multicast keyword to specify IPv4 multicast address prefixes. •Use the vrf keyword and vrf-name argument to specify the name of the VRF instance to associate with subsequent IPv4 address family configuration mode commands. |
Step 8 |
neighbor ip-address remote-as autonomous-system-number
Router(config-router-af)# neighbor 192.168.1.1 remote-as 65000 |
Adds the IP address of the neighbor in the specified autonomous system to the IPv4 multiprotocol BGP neighbor table of the local router. |
Step 9 |
neighbor ip-address activate
Router(config-router-af)# neighbor 192.168.1.1 activate |
Enables the neighbor to exchange prefixes for the IPv4 VRF address family with the local router. |
Step 10 |
neighbor ip-address inherit peer-policy policy-template-name
Router(config-router-af)# neighbor 192.168.1.1 inherit peer-policy SOO_POLICY |
Sends a peer policy template to a neighbor so that the neighbor can inherit the configuration. •In this example, the router is configured to send the peer policy template named SOO_POLICY to the 192.168.1.1 neighbor to inherit. If another peer policy template is indirectly inherited from SOO_POLICY, the indirectly inherited configuration will also be applied. Up to seven additional peer policy templates can be indirectly inherited from SOO_POLICY. |
Step 11 |
end
Router(config-router-af)# end |
Exits address family configuration mode and returns to privileged EXEC mode. |
Configuring a per Neighbor SoO Value Using a BGP neighbor Command
Perform this task on router PE2 in Figure 1 to configure an SoO value for the BGP neighbor at router CPE2 in Figure 1 using a neighbor command. Under address family IPv4 VRF, a neighbor is identified, and an SoO value is configured for the neighbor.
Direct configuration of the SoO value on a BGP neighbor overrides any inherited peer policy template configurations of the SoO value.
For a configuration example involving 4-byte autonomous system numbers, see the "Configuring a per Neighbor SoO Value Using a BGP neighbor Command and 4-Byte Autonomous System Numbers: Example" section.
Prerequisites
This task assumes that the task described in the "Verifying CEF and Configuring VRF Instances" section has been performed with appropriate changes to interfaces and IP addresses.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp autonomous-system-number
4. address-family ipv4 [unicast | multicast | vrf vrf-name]
5. neighbor {ip-address | peer-group-name} remote-as autonomous-system-number
6. neighbor ip-address activate
7. neighbor {ip-address | peer-group-name} soo extended-community-value
8. end
DETAILED STEPS
|
|
|
Step 1 |
enable
Router> enable |
Enables privileged EXEC mode. •Enter your password if prompted. |
Step 2 |
configure terminal
Router# configure terminal |
Enters global configuration mode. |
Step 3 |
router bgp autonomous-system-number
Router(config)# router bgp 50000 |
Enters router configuration mode for the specified routing process. |
Step 4 |
address-family ipv4 [unicast | multicast | vrf vrf-name]
Router(config-router)# address-family ipv4 vrf SOO_VRF |
Specifies the IPv4 address family and enters address family configuration mode. •Use the unicast keyword to specify the IPv4 unicast address family. By default, the router is placed in configuration mode for the IPv4 unicast address family if the unicast keyword is not specified with the address-family ipv4 command. •Use the multicast keyword to specify IPv4 multicast address prefixes. •Use the vrf keyword and vrf-name argument to specify the name of the VRF instance to associate with subsequent IPv4 address family configuration mode commands. |
Step 5 |
neighbor {ip-address | peer-group-name} remote-as autonomous-system-number
Router(config-router-af)# neighbor 192.168.2.1 remote-as 65000 |
Adds the IP address of the neighbor in the specified autonomous system to the IPv4 multiprotocol BGP neighbor table of the local router. |
Step 6 |
neighbor ip-address activate
Router(config-router-af)# neighbor 192.168.2.1 activate |
Enables the neighbor to exchange prefixes for the IPv4 VRF address family with the local router. •In this example, the external BGP peer at 192.168.2.1 is activated. Note If a peer group has been configured in Step 5, do not use this step because BGP peer groups are activated when any parameter is configured. For example, a BGP peer group is activated when an SoO value is configured using the neighbor soo command in Step 7. |
Step 7 |
neighbor {ip-address | peer-group-name} soo extended-community-value
Router(config-router-af)# neighbor 192.168.2.1 soo 65000:1 |
Sets the site-of-origin (SoO) value for a BGP neighbor or peer group. •In this example, the neighbor at 192.168.2.1 is configured with an SoO value of 65000:1. |
Step 8 |
end
Router(config-router-af)# end |
Exits address family configuration mode and returns to privileged EXEC mode. |
Configuring a per Neighbor SoO Value Using a BGP Peer Group
Perform this task on router PE1 in Figure 1 to configure an SoO value for the BGP neighbor at router CPE1 in Figure 1 using a neighbor command with a BGP peer group. Under address family IPv4 VRF, a BGP peer group is created and an SoO value is configured using a BGP neighbor command, and a neighbor is then identified and added as a peer group member. A BGP peer group member inherits the configuration associated with a peer group, which in this example, includes the SoO value.
Direct configuration of the SoO value on a BGP neighbor overrides any inherited peer group configurations of the SoO value.
Prerequisites
This task assumes that the task described in the "Verifying CEF and Configuring VRF Instances" section has been performed.
Restrictions
A BGP peer cannot inherit from a peer policy or session template and be configured as a peer group member at the same. BGP templates and BGP peer groups are mutually exclusive.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp autonomous-system-number
4. address-family ipv4 [unicast | multicast | vrf vrf-name]
5. neighbor peer-group-name peer-group
6. neighbor {ip-address | peer-group-name} soo extended-community-value
7. neighbor ip-address remote-as autonomous-system-number
8. neighbor ip-address activate
9. neighbor ip-address peer-group peer-group-name
10. end
DETAILED STEPS
|
|
|
Step 1 |
enable
Router> enable |
Enables privileged EXEC mode. •Enter your password if prompted. |
Step 2 |
configure terminal
Router# configure terminal |
Enters global configuration mode. |
Step 3 |
router bgp autonomous-system-number
Router(config)# router bgp 50000 |
Enters router configuration mode for the specified routing process. |
Step 4 |
address-family ipv4 [unicast | multicast | vrf vrf-name]
Router(config-router)# address-family ipv4 vrf SOO_VRF |
Specifies the IPv4 address family and enters address family configuration mode. •Use the unicast keyword to specify the IPv4 unicast address family. By default, the router is placed in configuration mode for the IPv4 unicast address family if the unicast keyword is not specified with the address-family ipv4 command. •Use the multicast keyword to specify IPv4 multicast address prefixes. •Use the vrf keyword and vrf-name argument to specify the name of the VRF instance to associate with subsequent IPv4 address family configuration mode commands. |
Step 5 |
neighbor peer-group-name peer-group
Router(config-router-af)# neighbor SOO_group peer-group |
Creates a BGP peer group. |
Step 6 |
neighbor {ip-address | peer-group-name} soo extended-community-value
Router(config-router-af)# neighbor SOO_group soo 65000:1 |
Sets the site-of-origin (SoO) value for a BGP neighbor or peer group. •In this example, the BGP peer group, SOO_group, is configured with an SoO value of 65000:1. |
Step 7 |
neighbor ip-address remote-as autonomous-system-number
Router(config-router-af)# neighbor 192.168.1.1 remote-as 65000 |
Adds the IP address of the neighbor in the specified autonomous system to the IPv4 multiprotocol BGP neighbor table of the local router. |
Step 8 |
neighbor ip-address activate
Router(config-router-af)# neighbor 192.168.1.1 activate |
Enables the neighbor to exchange prefixes for the IPv4 VRF address family with the local router. |
Step 9 |
neighbor ip-address peer-group peer-group-name
Router(config-router-af)# neighbor 192.168.1.1 peer-group SOO_group |
Assigns the IP address of a BGP neighbor to a peer group. |
Step 10 |
end
Router(config-router-af)# end |
Exits address family configuration mode and returns to privileged EXEC mode. |
Configuration Examples for BGP per Neighbor SoO Configuration
This section contains the following configuration examples:
•Configuring a per Neighbor SoO Value Using a BGP Peer Policy Template: Example
•Configuring a per Neighbor SoO Value with a 4-Byte Autonomous System Number Using a BGP Peer Policy Template: Example
•Configuring a per Neighbor SoO Value Using a BGP neighbor Command: Example
•Configuring a per Neighbor SoO Value Using a BGP neighbor Command and 4-Byte Autonomous System Numbers: Example
•Configuring a per Neighbor SoO Value Using a BGP Peer Group: Example
Configuring a per Neighbor SoO Value Using a BGP Peer Policy Template: Example
The following example shows how to create a peer policy template and configure an SoO value as part of the peer policy. After verifying that CEF is enabled and configuring a VRF instance named SOO_VRF, a peer policy template is created and an SoO value is configured as part of the peer policy. Under address family IPv4 VRF, a neighbor is identified and configured to inherit the peer policy that contains the SoO value.
ip vrf forwarding SOO_VRF
ip address 192.168.1.2 255.255.255.0
template peer-policy SOO_POLICY
address-family ipv4 vrf SOO_VRF
neighbor 192.168.1.1 remote-as 65000
neighbor 192.168.1.1 activate
neighbor 192.168.1.1 inherit peer-policy SOO_POLICY
Configuring a per Neighbor SoO Value with a 4-Byte Autonomous System Number Using a BGP Peer Policy Template: Example
The following example shows how to create a peer policy template and configure an SoO value using a 4-byte autonomous system number, 1.2 in asdot format, as part of the peer policy. Under address family IPv4 VRF, a neighbor is identified and configured to inherit the peer policy that contains the SoO value. This example requires Cisco IOS Release 12.4(24)T, or a later release.
template peer-policy SOO_POLICY
address-family ipv4 vrf SOO_VRF
neighbor 192.168.3.2 remote-as 1.14
neighbor 192.168.3.2 activate
neighbor 192.168.3.2 inherit peer-policy SOO_POLICY
The following example shows how to create a peer policy template and configure an SoO value using a 4-byte autonomous system number, 65538 in asplain format, as part of the peer policy. Under address family IPv4 VRF, a neighbor is identified and configured to inherit the peer policy that contains the SoO value. This example requires Cisco IOS Release 12.2(33)SRE, 12.2(33)XNE, or a later release.
template peer-policy SOO_POLICY
address-family ipv4 vrf SOO_VRF
neighbor 192.168.3.2 remote-as 65550
neighbor 192.168.3.2 activate
neighbor 192.168.3.2 inherit peer-policy SOO_POLICY
Configuring a per Neighbor SoO Value Using a BGP neighbor Command: Example
The following example shows how to configure an SoO value for a BGP neighbor. After checking that CEF is enabled, a VRF instance named SOO_VRF is configured, a neighbor is identified under address family IPv4 VRF, and an SoO value is configured for the neighbor.
ip vrf forwarding SOO_VRF
ip address 192.168.2.2 255.255.255.0
address-family ipv4 vrf SOO_VRF
neighbor 192.168.2.1 remote-as 65000
neighbor 192.168.2.1 activate
neighbor 192.168.2.1 soo 65000:1
Configuring a per Neighbor SoO Value Using a BGP neighbor Command and 4-Byte Autonomous System Numbers: Example
The following example shows how to configure an SoO value for a BGP neighbor. In this example, all BGP neighbors, route targets, and SoO values use 4-byte autonomous system numbers in asplain format. After checking that CEF is enabled, a VRF instance named SOO_VRF is configured with route targets. In a BGP router session a neighbor is identified under address family IPv4 VRF, and an SoO value is configured for the neighbor. This example requires Cisco IOS Release 12.4(24)T, or a later release.
route-target export 1.14:1
route-target import 1.14:1
ip vrf forwarding SOO_VRF
ip address 192.168.2.2 255.255.255.0
address-family ipv4 vrf SOO_VRF
neighbor 192.168.2.1 remote-as 1.14
neighbor 192.168.2.1 activate
neighbor 192.168.2.1 soo 1.14:1
Configuring a per Neighbor SoO Value Using a BGP Peer Group: Example
The following example shows how to configure an SoO value for a BGP peer group. After checking that CEF is enabled, a VRF instance named SOO_VRF is configured, a BGP peer group is configured under address family IPv4 VRF, an SoO value is configured for the peer group, a neighbor is identified, and the neighbor is configured as a member of the peer group.
ip vrf forwarding SOO_VRF
ip address 192.168.1.2 255.255.255.0
address-family ipv4 vrf SOO_VRF
neighbor SOO_GROUP peer-group
neighbor SOO_GROUP soo 65000:65
neighbor 192.168.1.1 remote-as 65000
neighbor 192.168.1.1 activate
neighbor 192.168.1.1 peer-group SOO_GROUP
Where to Go Next
•To read an overview of BGP, proceed to the "Cisco BGP Overview" module.
•To perform basic BGP feature tasks, proceed to the "Configuring a Basic BGP Network" module.
•To perform advanced BGP feature tasks, proceed to the "Configuring Advanced BGP Features" module.
•To configure BGP neighbor session options, proceed to the "Configuring BGP Neighbor Session Options" module.
•To perform internal BGP tasks, proceed to the "Configuring Internal BGP Features" module.
Additional References
The following sections provide references related to the BGP support for per neighbor SoO configuration feature.
Related Documents
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Cisco IOS commands |
Cisco IOS Master Commands List, All Releases |
BGP commands: complete command syntax, command mode, defaults, command history, usage guidelines, and examples |
Cisco IOS IP Routing: BGP Command Reference |
IP Switching commands: complete command syntax, command mode, defaults, command history, usage guidelines, and examples |
Cisco IOS IP Switching Command Reference |
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 releases, and feature sets, use Cisco MIB Locator found at the following URL: http://www.cisco.com/go/mibs |
Technical Assistance
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The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies. To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds. Access to most tools on the Cisco Support website requires a Cisco.com user ID and password. |
http://www.cisco.com/cisco/web/support/index.html |
Feature Information for BGP per Neighbor SoO Configuration
Table 1 lists the release history for this feature.
For information on a feature in this technology that is not documented here, see the "BGP Features Roadmap."
Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the command reference documentation.
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which Cisco IOS and Catalyst OS 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 software release that introduced support for a given feature in a given Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS software release train also support that feature.
Table 1 Feature Information for BGP per Neighbor SoO Configuration
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BGP per Neighbor SoO Configuration |
12.2(33)SB 12.2(33)SRB 12.4(11)T |
The BGP per neighbor SOO configuration feature simplifies the configuration of the site-of-origin (SoO) parameter. In Cisco IOS Release 12.4(9)T, 12.2(33)SRA, 12.2(31)SB2, and previous releases, the SoO parameter is configured using an inbound route map that sets the SoO value during the update process. The per neighbor SoO configuration introduces two new commands that can be configured in submodes under router configuration mode to set the SoO value. The following commands were introduced by this feature: neighbor soo, soo. |
BGP Support for 4-Byte ASN |
12.0(32)S12 12.0(32)SY8 12.2(33)SRE 12.2(33)XNE 12.4(24)T |
The BGP Support for 4-Byte ASN feature introduced support for 4-byte autonomous system numbers. Because of increased demand for autonomous system numbers, in January 2009 the IANA will start to allocate 4-byte autonomous system numbers in the range from 65536 to 4294967295. In Cisco IOS Release 12.0(32)SY8, 12.2(33)SRE, and 12.2(33)XNE, the Cisco implementation of 4-byte autonomous system numbers uses asplain as the default regular expression match and output display format for autonomous system numbers, but you can configure 4-byte autonomous system numbers in both the asplain format and the asdot format as described in RFC 5396. To change the default regular expression match and output display of 4-byte autonomous system numbers to asdot format, use the bgp asnotation dot command. In Cisco IOS Release 12.0(32)S12, and 12.4(24)T, the Cisco implementation of 4-byte autonomous system numbers uses asdot as the only configuration format, regular expression match, and output display, with no asplain support. The following sections provide information about this feature: •BGP Support for 4-Byte Autonomous System Numbers •Configuring a per Neighbor SoO Value with a 4-Byte Autonomous System Number Using a BGP Peer Policy Template: Example •Configuring a per Neighbor SoO Value Using a BGP neighbor Command and 4-Byte Autonomous System Numbers: Example The following commands were modified by this feature: bgp asnotation dot, bgp confederation identifier, bgp confederation peers, clear ip bgp, ip bgp-community new-format, ip extcommunity-list, match source-protocol, neighbor local-as, neighbor remote-as, neighbor soo, redistribute (IP), router bgp, set as-path, set extcommunity, set origin, soo, and all show ip bgp commands that display an autonomous system number. |
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