Juniper JUNOSE 11.2.X IP SERVICES, Руководство по настройке

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evaluates and processes each match clause and permits or denies routes based on the
match policy list configuration.
When you configure match policy lists, keep the following in mind:
•
A route map evaluates and processes all match statements within any match policy
list that it references.
• You can configure multiple match policy lists within a route map, and you can evaluate
each match policy list by using a logical AND or a logical OR.
•
You can reference match policy lists within a route map that also uses separate match
and set statements (that is, the statements are not part of the match policy list).
• All match policy lists within a route map match on the incoming attribute only.
ip match-policy-list
•
Use to create an IP match policy list and launch the match policy list configuration
mode.
•
Example
host1(config)# ip match-policy-list
host1(config-match-policy-list)#
•
Use the no version to delete the match policy list.
•
See ip match-policy-list.
Access Lists
An access list is a sequential collection of permit and deny conditions that you can use
to filter inbound or outbound routes. You can use different kinds of access lists to filter
routes based on either the prefix or the AS path.
Filtering Prefixes
To filter routes based on the prefix, you can do any of the following:
•
Define an access list with the access-list or ipv6 access-list command, and apply the
list to routes received from or passed to a neighbor with the neighbor distribute-list
command.
• Define a prefix list with the ip prefix-list command, and apply the list to routes received
from or passed to a neighbor with the neighbor prefix-list command.
•
Define a prefix tree with the ip prefix-tree command, and apply the list to routes
received from or passed to a neighbor with the neighbor prefix-tree command.
The router compares each route's prefix against the conditions in the list or tree,
one-by-one. If the first match is for a permit condition, the route is accepted or passed.
If the first match is for a deny condition, the route is rejected or blocked. The order of
conditions is critical because testing stops with the first match. If no conditions match,
the router rejects or blocks the address; that is, the last action of any list is an implicit
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JunosE 11.2.x IP Services Configuration Guide