Technical data

Using Technician Interface Software
8-74
303561-A Rev 00
Specifying AS Path Search Patterns
To retrieve only AS paths that contain a specific pattern of data, enter the
following command:
ip bgp_routes -R
<simplified_regular_expression>
The software transparently expands a <simplified_regular_expression> into a
fully detailed regular expression. The software then compares the pattern specified
by the regular expression to the data patterns in all AS paths currently known to
the router. The software retrieves a list of AS paths that contain the pattern you
specify in the <simplified_regular_expression>.
Table 8-8
describes <simplified_regular_expression> syntax, which applies only
to Release 11.0 or later versions of the router software. For detailed information
about the terms segment, set, and sequence, see Internet RFC 1654, “A Border
Gateway Protocol 4 (BGP-4).”
-R
Indicates that a
<simplfied_regular_expression> follows.
The software filters the output of the ip
bgp_routes command according to the
contents of the
<simplfied_regular_expression> .
<simplified_regular_expression>
Specifies a regular expresson in terms of
efficient, symbolic syntax. (More
information follows.)
Table 8-8. Simplified AS Pattern Matching Syntax
Symbol or
Operator Meaning
< Beginning of an AS SEQUENCE segment
> End of an AS SEQUENCE segment
{ Beginning of an AS SET segment
} End of an AS SET segment
<
seq
>{
set
} AS path containing a sequence in the first segment and a set in the
second segment
(continued)