Syslog-ng

syslog-ng is a powerful, massively configurable monitoring and logging daemon.

Emerge
Install :

Additional software
When using a system logger such as syslog-ng, it is a wise idea to install log rotation software to appropriately trim the logs as they consume more disk space. Logrotate is a fine option:

Configuration
The default configuration provided by the ebuild is quite minimal. For a more comprehensive configuration see the configuration provided for Hardened Gentoo in:

Files
The default source for syslog messages is:

If the system is running systemd, the default source needs to be changed to the following :

OpenRC
Add the syslog-ng daemon to the default runlevel so that logging starts on system boot:

Start the syslog-ng daemon now:

systemd
To start the syslog-ng daemon when the system boots enable the service:

To start the daemon now:

External resources

 * https://wiki.archlinux.org/index.php/syslog-ng