Brocade Communications Systems ICX 7250 series, Руководство по настройке

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Specifying a route map when configuring BGP4 network advertising
You can specify a route map when you configure a BGP4 network to be advertised. The device uses the route map to set or change
BGP4 attributes when creating a local BGP4 route.
NOTE
You must configure the route map before you can specify the route map name in a BGP4 network configuration; otherwise, the
route is not imported into BGP4.
To configure a route map, and use it to set or change route attributes for a network you define for BGP4 to advertise, enter commands
such as the following.
device(config)# route-map set_net permit 1
device(config-routemap set_net)# set community no-export
device(config-routemap set_net)# exit
device(config)# router bgp
device(config-bgp)# network 10.100.1.0/24 route-map set_net
The first two commands in this example create a route map named "set_net" that sets the community attribute for routes that use the
route map to "NO_EXPORT". The next two commands change the CLI to the BGP4 configuration level. The last command configures a
network for advertising from BGP4, and associates the "set_net" route map with the network. When BGP4 originates the
10.100.1.0/24 network, BGP4 also sets the community attribute for the network to "NO_EXPORT".
Changing the default local preference
When the device uses the BGP4 algorithm to select a route to send to the IP route table, one of the parameters the algorithm uses is the
local preference. Local preference indicates a degree of preference for a route relative to other routes. BGP4 neighbors can send the local
preference value as an attribute of a route in an UPDATE message.
Local preference applies only to routes within the local AS. BGP4 devices can exchange local preference information with neighbors who
also are in the local AS, but BGP4 devices do not exchange local preference information with neighbors in remote autonomous systems.
The default local preference is 100. For routes learned from EBGP neighbors, the default local preference is assigned to learned routes.
For routes learned from IBGP neighbors, the local preference value is not changed for the route.
When the BGP4 algorithm compares routes on the basis of local preferences, the route with the higher local preference is chosen.
NOTE
To set the local preference for individual routes, use route maps.
To change the default local preference to 200, enter the following command.
device(config-bgp)# default-local-preference 200
Syntax: [no] default-local-preference num
The num parameter indicates the preference and can be a value from 0 - 4294967295.
Using the IP default route as a valid next-hop for a BGP4 route
By default, the device does not use a default route to resolve a BGP4 next-hop route. If the IP route lookup for the BGP4 next-hop does
not result in a valid IGP route (including static or direct routes), the BGP4 next-hop is considered to be unreachable and the BGP4 route
is not used.
Optional BGP4 configuration tasks
Brocade FastIron Layer 3 Routing Configuration Guide
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