Juniper Networks J-Series manual Common Regular Expression Operators and the Terms They Match

Chapter 8: Monitoring Events and Managing System Log Files

Table 83: Common Regular Expression Operators and the Terms They Match

Regular Expression Operator	Matching Terms
. (period)	One instance of any character except the space.
	For example, .in matches messages with win or windows.
* (asterisk)	Zero or more instances of the immediately preceding term.
	For example, tre* matches messages with tree, tread or trough.
+ (plus sign)	One or more instances of the immediately preceding term.
	For example, tre+ matches messages with tree or tread but not trough.
? (question mark)	Zero or one instance of the immediately preceding term.
	For example, colou?r matches messages with or color or colour.
(pipe)	One of the terms that appear on either side of the pipe operator.
	For example, greay matches messages with either grey or gray.
! (exclamation point)	Any string except the one specified by the expression, when the exclamation
	point appears at the start of the expression. Use of the exclamation point is
	specific to JUNOS.
^ (caret)	The start of a line, when the caret appears outside square brackets.
	For example, ^T matches messages with This line and not with On this line.
$ (dollar sign)	Strings at the end of a line.
	For example, :$ matches messages with the following: and not with 2:00.
[] (paired square brackets)	One instance of one of the enclosed alphanumeric characters. To indicate a
	range of characters, use a hyphen (-) to separate the beginning and ending
	characters of the range.
	For example, [0-9]matches messages with any number.
() (paired parentheses)	One instance of the evaluated value of the enclosed term. Parentheses are used
	to indicate the order of evaluation in the regular expression.
	For example, dev(/ice) matches messages with dev/ or device.

Before You Begin

Before you begin configuring and monitoring system log messages, complete the following tasks:

■Establish basic connectivity. See the Getting Started Guide for your router.

■Configure network interfaces. See the J-series Services Router Basic LAN and WAN Access Configuration Guide.

Before You Begin ■ 159