# Installing rsyslog from the source repository

In most cases, people install rsyslog either via a package or use an “official” distribution tarball to generate it. But there may be situations where it is desirable to build directly from the source repository. This is useful for people who would like to participate in development or who would like to use the latest, not-yet-released code. The later may especially be the case if you are asked to try out an experimental version.

Building from the repository is not much different than building from the source tarball, but some files are missing because they are output files and thus do not belong into the repository.

## Obtaining the Source

First of all, you need to download the sources. Rsyslog is kept in git. The “Where to find the rsyslog source code” page on the project site will point you to the current repository location.

After you have cloned the repository, you are in the master branch by default. This is where we keep the devel branch. If you need any other branch, you need to do a “git checkout –track -b branch origin/branch”. For example, the command to check out the beta branch is “git checkout –track -b beta origin/beta”.

## Prequisites

Note

The rsyslog project maintains multiple rsyslog docker development environment images. These images have been configured specifically for use with rsyslog and are recommended over your own build environment. Rsyslog docker development images are named with the `rsyslog_dev_` prefix, followed by the distro name.

Warning

If you plan to copy the binary for use outside of the container you need to make sure to use an image of the same distro/version when building rsyslog.

To build the compilation system, you need

- GNU autotools (autoconf, automake, …)
- libtool
- pkg-config

Unfortunately, the actual package names vary between distributions. Doing a search for the names above inside the packaging system should lead to the right path, though.

If some of these tools are missing, you will see errors like this one:

    checking for SYSLOG_UNIXAF support... yes
    checking for FSSTND support... yes
    ./configure: line 25895: syntax error near unexpected token `RELP,'
    ./configure: line 25895: ` PKG_CHECK_MODULES(RELP, relp >= 0.1.1)'

The actual error message will vary. In the case shown here, pkg-config was missing.

Important: the build dependencies must be present before creating the build environment is begun. Otherwise, some hard to interpret errors may occur. For example, the error above will also occur if you install pkg-config, but after you have run autoreconf. So be sure everything is in place before you create the build environment.

## Creating the Build Environment

This is fairly easy: just issue “autoreconf -fvi”, which should do everything you need. Once this is done, you can follow the usual ./configure steps just like when you downloaded an official distribution tarball (see the rsyslog install guide, starting at step 2, for further details about that).

See also

Help with configuring/using `Rsyslog`:

- Mailing list - best route for general questions
- GitHub: rsyslog source project - detailed questions, reporting issues that are believed to be bugs with `Rsyslog`
- Stack Exchange (View, Ask) - experimental support from rsyslog community

See also

Contributing to `Rsyslog`:

- Source project: rsyslog project README.
- Documentation: rsyslog-doc project README

Copyright 2008-2020 Rainer Gerhards (Großrinderfeld), and Others.