Introduction

The log files size must be controlled because their size always grows over time. Each system has limited resources, and too large logs lead to performance and memory problems. Linux solves this problem with a concept called logrotate. **The logrotate is the system daemon that rotates, compresses, and mails system logs.

This tutorial shows you how to:

• View logrotate configuration, where is stored general configuration, and where are records of application-specific setup.
• Create standard logrotate configuration for fictional log of some custom app.
• Create system independent logrotate configuration for same log.

Prerequisites

You will need:

• Basic knowledge of how to work with Linux command line.
• Ubuntu 20.04 distribution including the non-root user with sudo access.
• Basic of Linux logs and their configuration.

Step 1 — Viewing Logrotate configuration

System logs in Ubuntu 20.04 with a default configuration maintains the daemon logrotate. This daemon uses configuration files that specify all rotation details for each application. The configuration consist of the following parts:

• /etc/logrotate.conf: This is a most general configuration file with default setup.
• /etc/logrotate.d: This is a directory that includes files for specific application rotation. Each such application has there own configuration file. Otherwise, application logs use general configuration.

We will view both configuration possibilities.

General logrotate configuration

As first, let's view more general configuration file /etc/logrotate.conf.

Print the content of file /etc/logrotate.conf with utility cat:

$ cat /etc/rsyslog.conf