3Com Switch 7700 Configuration Manual page 185

The deny argument specifies that the apply clauses are not executed. If a route
satisfies all the if-match clauses of the node, the node denies the route and the
route does not take the test of the next node. If a route does not satisfy all the
if-match clauses of the node, however, the route takes the test of the next node.
The router tests the route against the nodes in the route policy in sequence, once
a node is matched, the route policy filtering is passed.
By default, the route policy is not defined.
If multiple nodes are defined in a route policy, at least one of them should be in
permit mode. Apply the route policy to filter routing information. If the routing
information does not match any node, the route policy denies the routing
information. If all the nodes in the route policy are in deny mode, all routing
information will be denied by the route policy.
Defining If-match Clauses for a Route Policy
The if-match clauses define the matching rules that the routing information must
satisfy to pass the route policy. The matching objects are attributes of the routing
information.
Perform the following configurations in route policy view.
Table 133 Defining If-match Conditions
Operation
Match the AS path domain of the BGP routing
information
Cancel the matched AS path domain of the
BGP routing information
Match the community attribute of the BGP
routing information
Cancel the matched community attribute of
the BGP routing information
Match the destination address of the routing
information
Cancel the matched destination address of the
routing information set by the ACL
Match the next-hop interface of the routing
information
Cancel the matched next-hop interface of the
routing information
Match the next-hop of the routing
information
Cancel the matched next-hop of the routing
information set by the address prefix list
Match the routing cost of the routing
information
Cancel the matched routing cost of the
routing information
Match the tag domain of the OSPF routing
information
IP Routing Policy
Command
if-match as-path acl-number
undo if-match as-path
if-match community {
standard-community-number [ whole-match
] | extended-community-number }
undo if-match community
if-match { acl | ip-prefix }
undo if-match [ acl acl-number | ip-prefix
ip-prefix-name ]
if-match interface { interface-type
interface-number }
undo if-match interface
if-match ip next-hop { acl acl-number |
ip-prefix ip-prefix-name }
undo if-match ip next-hop [ip-prefix
ip-prefix-name ]
if-match cost cost
undo if-match cost
if-match tag value
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