Regular Expression Checker/Generator

This is a regular expression checker especially programmed for rsyslog. Rsyslog uses POSIX ERE (and optionally BRE) expressions. This checker works with the php POSIX ERE functions. So in theory, there can be a difference between what the engine included in rsyslog (clib) and this web app does. However, in practice the results should be fairly the same.

Note: you need at least rsyslog version 3.19.5 (for v3) or 4.1.5 (for v4 and above) to use ERE expressions.

To use this tool, paste a sample of the field in question into "Sample Log Line", write your regular expression and press the button ;) You will then see what the regular expression engine extracts. Also, the result fields contain a property replacer field definition in theory suitable for copying and pasting into your rsyslog.conf.

Please note: If you want to use the output of the result fields in conjunction with a quoted string, please use our Constant String Escaper as well. Un-escaped regular expressions in a quoted string will result in configuration errors.

rsyslog property
Regular Expression
Submatch to Use
Nomatch Mode
Sample Log Line
(use a single line,
wraps for readability)