Alcatel-Lucent OmniAccess 5740 - Page 536

Protocol Independent Features
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OmniAccess 5740 Unified Services Gateway CLI Configuration Guide
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C
ONFIGURE PREFIX-LIST
IP Prefix-list provides prefix based filtering mechanism. In addition to the access-
list functionality, IP Prefix-list has prefix length range specification and sequential
number specification. You can add or delete prefix based filters to arbitrary points
of prefix-list using sequential number specification.
E
XAMPLE
In the following example, permit updates for any network with a prefix mask length
less than or equal to 23. Denies all network updates with a network mask length
greater than 23.
ALU(config)# ip prefix-list test permit 0.0.0.0/0 le 23
Note: Less than or equal to prefix numbers and greater than or equal to prefix numbers can
be used together. The order of the le and ge commands does not matter.
C
ONFIGURE AS-PATH ACCESS-LIST
A regular expression is a pattern used to match against an input string. In case of
BGP, we can have a regular expression to match particular autonomous system
path. This is used to filter updates from neighbors.
E
XAMPLE
In the following example, the IP as-path access-list commands create an as-path
access list named '1' to deny only those routes that include paths from or through
autonomous systems 100:
ALU(config)# ip as-path access-list 1 deny _100_
Command (in CM) Description
ip prefix-list <name> [seq <1-
4294967294>] {{deny|permit}
<ip-address/prefix-length>
{ge|le} <0-32>|description
<line>}
This command is used to configure a
Prefix-list.
Command (in CM) Description
ip as-path access-list <1-199>
{deny|permit} <regular-
expression>
This command is used to configure AS-
path Access-list.