Juniper JUNOSE 11.3, Configuration Manual

Page: 69 / 632

The filtering is performed before redirection. In the following example, the cnfgfltr.txt file
will contain the output of
show config include-defaults beginning with the first occurrence
of the string inter .
host1# show config include-defaults &> cnfgfltr.txt | begin inter
Regular Expressions
A regular expression uses special characters—often referred to as metacharacters—to
define a pattern that is compared with an input string. You can use regular expressions
to filter the output of
show commands and to define AS-path access lists and community
lists to more easily filter routes.
For examples of using regular expressions with AS-path access lists and community lists,
see
JunosE IP Services Configuration Guide .
Metacharacters
Table 5 on page 39 describes the metacharacters supported for regular expression
pattern-matching.
Table 5: Supported Regular Expression Metacharacters
Description Metacharacter
Matches the beginning of the input string.
Alternatively, when used as the first character within brackets—[^ ]—matches
any number except the ones specified within the brackets.
^
Matches the end of the input string. $
Matches any single character, including white space. .
Matches 0 or more sequences of the immediately previous character or pattern. *
Matches 1 or more sequences of the immediately previous character or pattern. +
Matches 0 or 1 sequence of the immediately previous character or pattern. ?
Specifies patterns for multiple use when followed by one of the multiplier
metacharacters: asterisk *, plus sign +, or question mark ? ()
Matches any enclosed character; specifies a range of single characters. [ ]
Used within brackets to specify a range of AS or community numbers. – (hyphen)
Matches a ^, a $, a comma, a space, a {, or a }. Placed on either side of a string
to specify a literal and disallow substring matching. Numerals enclosed by
underscores can be preceded or followed by any of the characters listed above. _ (underscore)
Matches characters on either side of the metacharacter; logical OR. |
39 Copyright © 2010, Juniper Networks, Inc.
Chapter 2: Command-Line Interface