Installing a Logger

Introduction

In case you ever need to view important system messages, it is a wise idea to install a system logger. System loggers create log files that contain system messages, and stores these logs in /var/log. Several different loggers exist. Listed below are some of the more commonly used loggers:

• Metalog - "Metalog is a modern replacement for syslogd and klogd. The logged messages can be dispatched according to their facility, urgency, program name and/or Perl-compatible regular expressions." This is a good, light-weight logger that is often used for desktop systems. (Metalog homepage)
• Syslog-ng - "syslog-ng is the trusted log management infrastructure for hundreds of thousands of users worldwide. Organizations use syslog-ng to reliably and securely collect, process and store log messages from across their IT environments." syslog-ng is often used when more advanced logging functionality is required, and is highly customizable. (Syslog-ng homepage)
• Rsyslog - "rsyslog is an alternative logger to syslog-ng and offers many benefits over syslog-ng. rsyslog is also the default logger for the latest versions of Red Hat Enterprise Linux, as well as many other Linux distributions." (Arch wiki page)

Installation and adding to runlevel

To install a logger, run the following command:

root #  emerge --ask metalog

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild  N     ] app-admin/metalog-3-r1  USE="unicode" 353 kB

Total: 1 package (1 new), Size of downloads: 353 kB
Would you like to merge these packages? [Yes/No] #  yes

After installing the logger, we have to add its initialization script to RC’s default runlevel. The default runlevel, defined at /etc/runlevels/default, contains symbolic links to all system initialization scripts that are run by default. To add the logger to the runlevel and then start the logger, run the following:

root #  rc-update add metalog default
 * service metalog added to runlevel default
root #  rc
 * Starting metalog ...

Stopping the service

If, for whatever reason, you need to stop a service manually, you can run its initialization script directly from /etc/init.d:

root # /etc/init.d/metalog stop
 * Stopping metalog ...