Alcatel-Lucent 6850-48 Guida Di Riferimento

BGP Commands

page 44-102

OmniSwitch CLI Reference Guide

Configures the priority for processing regular expressions in an AS path list.

ip bgp policy aspath-list name “regular_expression” priority value

The AS path name, e.g., InboundAspath, ranging from 0 to 70 charac-
ters, or a value of none. The AS path name is case sensitive. 

A regular expression, e.g., “^100 200$” where 100 (followed by a 
space) represents the beginning of the list and 200 represents the end. 
The regular expression must be enclosed by quotation marks.

A priority value, e.g., 1, assigned to the policy action. Valid priority 
range is from 1 - 255.

OmniSwitch 6850, 6855, 9000, 9000E

• A regular expression consists of a character string presented in the form of a pattern, e.g., ^100 200$. 

 for a table of valid regular expression characters 

(metacharacters). See also “Configuring BGP” in your Advanced Routing Guide for more information 
on using regular expressions in BGP commands.

• This command specifies the priority of an AS path list filter being applied to a peer’s inbound and 

outbound routes configured via the 

 and 

commands. The AS path list filters routes based on one or more regular expressions, as shown in the 
example below. If the route matches the AS path list filter, then the permit or deny action (i.e., policy) 
associated with the regular expression applies, but only in the order designated by the priority value.

• The higher the priority value specified in the command, the later the matching is processed. For exam-

ple, regular expressions with a priority of 1 (the default) are processed before an expression assigned a 
priority of 3. When regular expressions have an equal priority, the processing order is indeterminate.

• General or more specific AS path list information can be displayed by varying the use of the 

 command.

-> ip bgp policy aspath-list InboundAspath “^100 200$” priority 1

-> ip bgp policy aspath-list OutboundAspath “^300 400$” priority 5

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