Use this documentation with care! It describes
the outdated version 7, which was actively
developed around 2014 and is considered dead by the
This documentation reflects the latest update of the v7-stable branch. It describes the 7.6.8 version, which was never released. As such, it contains some content that does not apply to any released version.
To obtain the doc that properly matches your installed v7 version, obtain the doc set from your distro. Each version of rsyslog contained the version that exactly matches it.
As general advise, it is strongly suggested to upgrade to the current version supported by the rsyslog project. The current version can always be found on the right-hand side info box on the rsyslog web site.
Note that there is only limited rsyslog community support available for the outdated v7 version (officially we do not support it at all, but we usually are able to answer simple questions). If you need to stick with v7, it probably is best to ask your distribution for support.
String constants are necessary in many places: comparisons, configuration parameter values and function arguments, to name a few important ones.
In constant strings, special characters are escape by prepending a backslash in front of them – just in the same way this is done in the C programming language or PHP.
If in doubt how to properly escape, use the RainerScript String Escape Online Tool.