Defining neighbor distribute lists, Defining route maps – Brocade BigIron RX Series Configuration Guide User Manual
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BigIron RX Series Configuration Guide
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Defining neighbor distribute lists
A neighbor distribute list is a list of BGP4 address filters or ACLs that filter the traffic to or from a
neighbor.
To configure a distribute list that uses ACL 1, enter a command such as the following.
BigIron RX(config-bgp)# neighbor 10.10.10.1 distribute-list 1 in
This command configures the device to use ACL 1 to select the routes that the device will accept
from neighbor 10.10.10.1.
Syntax: neighbor <ip-addr> distribute-list <name-or-num> in | out
The <ip-addr> parameter specifies the neighbor.
The
ACL.
The in | out parameter specifies whether the distribute list applies to inbound or outbound routes.
•
in – controls the routes the device will accept from the neighbor.
•
out – controls the routes sent to the neighbor.
Defining route maps
A route map is a named set of match conditions and parameter settings that the router can use to
modify route attributes and to control redistribution of the routes into other protocols. A route map
consists of a sequence of instances. If you think of a route map as a table, an instance is a row in
that table. The router evaluates a route according to a route map’s instances in ascending
numerical order. The route is first compared against instance 1, then against instance 2, and so
on. As soon as a match is found, the router stops evaluating the route against the route map
instances.
Route maps can contain match statements and set statements. Each route map contains a
“permit” or “deny” action for routes that match the match statements.
•
If the route map contains a permit action, a route that matches a match statement is
permitted; otherwise, the route is denied.
•
If the route map contains a deny action, a route that matches a match statement is denied.
•
If a route does not match any match statements in the route map, the route is denied. This is
the default action. To change the default action, configure the last match statement in the last
instance of the route map to “permit any any.”.
•
If there is no match statement, the software considers the route to be a match.
•
For route maps that contain address filters, AS-path filters, or community filters, if the action
specified by a filter conflicts with the action specified by the route map, the route map’s action
takes precedence over the individual filter’s action.
If the route map contains set statements, routes that are permitted by the route map’s match
statements are modified according to the set statements.
Match statements compare the route against one or more of the following:
•
The route’s BGP4 MED (metric)
•
A sequence of AS-path filters