Brocade Communications Systems FastIron X Series User Manual

To lter on a specic single-character value, enter the character for the as-path parameter. For example, to lter on AS-paths that contain
the letter "z", enter the following command:
device(config-bgp-router)# ip as-path access-list acl1 permit z
To
lter on a string of multiple characters, enter the characters in brackets. For example, to lter on AS-paths that contain "x", "y", or "z",
enter the following command.
device(config-bgp-router)# ip as-path access-list acl1 permit [xyz]
BGP4 Special characters
When you enter a single-character expression or a list of characters, you also can use the special characters listed in "Using regular
expressions." The description for each character includes an example. Some special characters must be placed in front of the characters
they control and others must be placed after the characters they control. The examples show where to place the special character.
TABLE 90 BGP4 special characters for regular expressions
Character Operation
. The period matches on any single character, including a blank space. For
example, the following regular expression matches for "aa", "ab", "ac", and
so on, but not just "a".
a.
* The asterisk matches on zero or more sequences of a pattern. For
example, the following regular expression matches on an AS-path that
contains the string "1111" followed by any value:
1111*
+ The plus sign matches on one or more sequences of a pattern. For
example, the following regular expression matches on an AS-path that
contains a sequence of "g"s, such as "deg", "degg", "deggg", and so on:
deg+
? The question mark matches on zero occurrences or one occurrence of a
pattern. For example, the following regular expression matches on an AS-
path that contains "dg" or "deg":
de?g
^ A caret (when not used within brackets) matches on the beginning of an
input string. For example, the following regular expression matches on an
AS-path that begins with "3":
^3
$ A dollar sign matches on the end of an input string. For example, the
following regular expression matches on an AS-path that ends with "deg":
deg$
_ An underscore matches on one or more of the following:
• , (comma)
• { (left curly brace)
• } (right curly brace)
• ( (left parenthesis)
• ) (right parenthesis)
• The beginning of the input string
• The end of the input string
• A blank space
Filtering
FastIron Ethernet Switch Layer 3 Routing
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Brocade Communications Systems FastIron X Series Specifications

General

Brand	Brocade Communications Systems
Model	FastIron X Series
Category	Switch
Language	English