Configure Redistribution to BGP
Configure a redistribution entry to announce routes of a certain source protocol type into the BGP domain such as: DvR routes, static routes, Routing Information Protocol (RIP) routes, or direct routes. Use a route policy to control the redistribution of routes.
Note
When a route map with attributes set to origin and local-pref is applied to the BGP redistribute command, the attributes are not applied to the redistributed routes.
Before you begin
-
If required, a route policy exists.
-
You can configure BGP on a VRF instance the same way you configure the GlobalRouter, except that you must use VRF Router Configuration mode and the prefix ip bgp. The VRF must have an RP Trigger of BGP.
Note
Route refresh is not currently supported on non-default VRFs.
-
Before you redistribute DvR host routes to BGP, you must disable BGP aggregation and BGP auto-summarization of networks, using the commands no ip bgp aggregation enable and no ip bgp auto-summary respectively.
Disabling these settings ensures that all the DvR host routes are correctly advertised into BGP and are not summarized.
Note
When applying a route map to an inter-vrf redistribution, the route map and any associated IP prefix lists must be configured first on the source VRF before configuring the redistribute policy on the destination VRF.
Inter-vrf redistribution is not supported on IPv6 routes.
Procedure
-
Create a redistribution
instance:
redistribute <direct|dvr|ipv6-direct|ipv6-isis|ipv6-static|isis|ospf|ospfv3|rip|ripng|static>
Note
Redistribution of ripng routes into BGP is supported only on VRF 0.
Examples
Redistribute direct routes from the VRF instance source1 into BGP, in the GRT context.
Create a redistribution instance:
Switch:1>enable Switch:1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch:1(config)#router bgp Switch(router-bgp)#redistribute direct vrf-src source1
If required, specify a route policy to govern redistribution:
Switch(router-bgp)# redistribute direct route-map policy1 vrf-src source1
If required, configure the route metric:
Switch:1(router-bgp)# redistribute direct metric 4 vrf-src source1
Enable the instance:
Switch:1(router-bgp)# redistribute direct enable vrf-src source1
Exit BGP Router Configuration mode:
Switch:1(router-bgp)# exit
Apply the redistribution instance configuration:
Switch:1(config)# ip bgp apply redistribute direct vrf-src source1
Redistribute DvR routes from the GRT to BGP:
Switch:1>enable Switch:1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch:1(config)#router bgpSwitch:1(router-bgp)#redistribute dvr Switch:1(router-bgp)#redistribute dvr enable Switch:1(router-bgp)#exit Switch:1(config)#ip bgp apply redistribute dvr
View the host routes (including DvR host routes) that are redistributed from the GRT to BGP:
Switch:1(config)#show ip bgp imported-routes vrf vrf1
=================================================================================
BGP Imported Routes - VRF vrf1
=================================================================================
ROUTE METRIC COMMUNITY LOCALPREF NEXTHOP ORIGIN
---------------------------------------------------------------------------------
192.0.2.1/255.255.255.0 0 0 100 198.51.100.1 INC
192.0.2.2/255.255.255.0 0 0 100 198.51.100.1 INC
192.0.2.3/255.255.255.0 0 0 100 198.51.100.1 INC
...
...
...
3 out of 763 Total Num of imported routes displayed
Redistribute DvR routes to BGP for the specific VRF instance vrf1:
Switch:1>enable Switch:1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch:1(config)#router vrf vrf1 Switch:1(router-vrf)#ip bgp redistribute dvr Switch:1(router-vrf)#ip bgp redistribute dvr enable Switch:1(router-vrf)#exit Switch:1(config)#ip bgp apply redistribute dvr vrf vrf1
View the DvR host routes that are redistributed to BGP for vrf vrf1:
Switch:1(config)#show ip bgp imported-routes vrf vrf1
=================================================================================
BGP Imported Routes - VRF vrf1
=================================================================================
ROUTE METRIC COMMUNITY LOCALPREF NEXTHOP ORIGIN
---------------------------------------------------------------------------------
192.0.2.4/255.255.255.0 0 0 100 203.0.113.1 INC
192.0.2.5/255.255.255.0 0 0 100 203.0.113.1 INC
192.0.2.6/255.255.255.0 0 0 100 203.0.113.1 INC
192.0.2.7/255.255.255.0 0 0 100 203.0.113.1 INC
192.0.2.8/255.255.255.0 0 0 100 203.0.113.1 INC
...
...
...
5 out of 675 Total Num of imported routes displayed
This example demonstrates redistribution of inter-VRF routes (both direct and DvR routes) to BGP, with a route policy configured.
Redistribute inter-VRF DvR routes between VRFs (with VRF IDs 10 and 30), to BGP.
Switch:1>enable Switch:1#configure terminal Switch:1(config)#router vrf 10 Switch:1(router-vrf)#ip prefix-list "test10" 192.0.2.0/24 ge 25 le 32 Switch:1(router-vrf)#route-map "test10" 1 Switch:1(router-vrf)#permit Switch:1(router-vrf)#enable Switch:1(router-vrf)#match network "test10" Switch:1(router-vrf)#set metric 99 Switch:1(router-vrf)#exit Switch:1(config)#router vrf 30 Switch:1(router-vrf)#ip bgp redistribute direct vrf-src 10 Switch:1(router-vrf)#ip bgp redistribute direct enable vrf-src 10 Switch:1(router-vrf)#ip bgp redistribute dvr vrf-src 10 Switch:1(router-vrf)#ip bgp redistribute dvr route-map "test10" vrf-src 10 Switch:1(router-vrf)#ip bgp redistribute dvr enable vrf-src 10 Switch:1(router-vrf)#exit Switch:1(config)#ip bgp apply redistribute direct vrf 30 vrf-src 10 Switch:1(config)#ip bgp apply redistribute dvr vrf 30 vrf-src 10
Variable Definitions
The following table defines parameters for the redistribute and ip bgp apply redistribute commands.
|
Variable |
Value |
|---|---|
|
<direct | dvr | ipv6-direct | ipv6-isis | ipv6-static | isis | ospf | ospfv3 | rip | ripng| static > |
Specifies the type of routes to redistribute (the protocol source). |
|
enable |
Enables the BGP route redistribution instance. |
|
metric <0-65535> |
Configures the metric to apply to redistributed routes. |
|
metric-type live-metric |
Configures the metric type to apply to redistributed routes. When you enable the live-metric option, when BGP redistributes static, RIP, OSPF, IS-IS, or DvR routes, the metric value is taken from the routing table and is set to the Path attributes as a MED value. By default, this option is disabled, which means the BGP MED value is not derived from the metric in the routing table. |
|
route-map WORD<0-64> |
Configures the route policy to apply to redistributed routes. |
|
vrf WORD<1–16> |
Specifies the name of a VRF instance. |
|
vrf-src WORD<1-16> |
Specifies the source VRF instance by name for route redistribution. |