Configuration Overview - IBM RackSwitch G8000 Application Manual

Configuration Overview

© Copyright IBM Corp. 2011
To configure route maps, you need to do the following:
1. Define a network filter.
RS G8000(config)# ip match-address 1 <IPv4 address> <IPv4 subnet mask>
RS G8000(config)# ip match-address 1 enable
Enter a filter number from 1 to 256. Specify the IPv4 address and subnet mask of
the network that you want to match. Enable the network filter. You can distribute
up to 256 network filters among 32 route maps each containing eight access
lists.
2. (Optional) Define the criteria for the access list and enable it.
Specify the access list and associate the network filter number configured in
Step 1.
RS G8000(config)# route-map 1
RS G8000(config-route-map)# access-list 1 match-address 1
RS G8000(config-route-map)# access-list 1 metric <metric value>
RS G8000(config-route-map)# access-list 1 action deny
RS G8000(config-route-map)# access-list 1 enable
Steps 2 and 3 are optional, depending on the criteria that you want to match. In Step
2, the network filter number is used to match the subnets defined in the network
filter. In Step 3, the autonomous system number is used to match the subnets. Or,
you can use both (Step 2 and Step 3) criteria: access list (network filter) and access
path (AS filter) to configure the route maps.
3. (Optional) Configure the AS filter attributes.
RS G8000(config-route-map)# as-path-list 1 as 1
RS G8000(config-route-map)# as-path-list 1 action deny
RS G8000(config-route-map)# as-path-list 1 enable
4. Set up the BGP attributes.
If you want to overwrite the attributes that the peer router is sending, define the
following BGP attributes:
– Specify the AS numbers that you want to prepend to a matched route and
the local preference for the matched route.
– Specify the metric [Multi Exit Discriminator (MED)] for the matched route.
RS G8000(config-route-map)# as-path-preference <AS number>
RS G8000(config-route-map)# local-preference <local preference number>
RS G8000(config-route-map)# metric <metric value>
5. Enable the route map.
RS G8000(config-route-map)# enable
RS G8000(config-route-map)# exit
Chapter 21. Border Gateway Protocol
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