Configuration Guide Manual

706 Brocade TurboIron 24X Series Configuration Guide
53-1003053-01
Filtering
+ 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
For example, the following regular expression matches on “100” but not on “1002”, “2100”,
and so on.
_100_
[
] Square brackets enclose a range of single-character patterns. For example, the following
regular expression matches on an AS-path that contains “1”, “2”, “3”, “4”, or “5”:
[1-5
]
You can use the following expression symbols within the brackets. These symbols are allowed
only inside the brackets:
• ^ – The caret matches on any characters except the ones in the brackets. For example,
the following regular expression matches on an AS-path that does not contain “1”, “2”,
“3”, “4”, or “5”:
[^1-5
]
• - The hyphen separates the beginning and ending of a range of characters. A match
occurs if any of the characters within the range is present. See the example above.
| A vertical bar (sometimes called a pipe or a “logical or”) separates two alternative values or
sets of values. The AS-path can match one or the other value. For example, the following
regular expression matches on an AS-path that contains either “abc” or “defg”:
(abc)|(defg)
NOTE: The parentheses group multiple characters to be treated as one value. See the
following row for more information about parentheses.
( ) Parentheses allow you to create complex expressions. For example, the following complex
expression matches on “abc”, “abcabc”, or “abcabcabcdefg”, but not on “abcdefgdefg”:
((abc)+)|((defg)?)
TABLE 103 BGP4 special characters for regular expressions (Continued)
Character Operation