Specifying a list of networks to advertise – Brocade TurboIron 24X Series Configuration Guide User Manual

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Brocade TurboIron 24X Series Configuration Guide

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Optional configuration tasks

multi-as – Load sharing is enabled for paths from different ASs.

By default, load sharing applies to EBGP and IBGP paths, and does not apply to paths from
different neighboring ASs.

Specifying a list of networks to advertise

By default, the router sends BGP4 routes only for the networks you identify using the network
command or that are redistributed into BGP4 from RIP or OSPF. You can specify up to 600
networks.

To specify a network to be advertised, use either of the following methods.

NOTE

The exact route must exist in the IP route table before the Layer 3 Switch can create a local BGP
route.

To configure the Layer 3 Switch to advertise network 10.157.22.0/24, enter the following
command.

TurboIron(config-bgp-router)#network 10.157.22.0 255.255.255.0

Syntax: network <ip-addr> <ip-mask> [nlri multicast | unicast | multicast unicast]

[route-map <map-name>] | [weight <num>] | [backdoor]

The <ip-addr> is the network number and the <ip-mask> specifies the network mask.

The nlri multicast | unicast | multicast unicast parameter specifies whether the neighbor is a
multicast neighbor or a unicast neighbor. Optionally, you also can specify unicast if you want the
Layer 3 Switch to exchange unicast (BGP4) routes as well as multicast routes with the neighbor.
The default is unicast only.

The route-map <map-name> parameter specifies the name of the route map you want to use to set
or change BGP4 attributes for the network you are advertising. The route map must already be
configured.

The weight <num> parameter specifies a weight to be added to routes to this network.

The backdoor parameter changes the administrative distance of the route to this network from the
EBGP administrative distance (20 by default) to the Local BGP weight (200 by default), thus tagging
the route as a backdoor route. Use this parameter when you want the router to prefer IGP routes
such as RIP or OSPF routes over the EBGP route for the network.

Specifying a route map name when configuring BGP4 network information

You can specify a route map as one of the parameters when you configure a BGP4 network to be
advertised. The Layer 3 Switch can use the route map to set or change BGP4 attributes when
creating a local BGP4 route.

To configure network information and use a route map to set or change BGP4 attributes, use the
following CLI method.

NOTE

You must configure the route map before you can specify the route map name in a BGP4 network
configuration.

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