Linux Up Skill - Day 18

Moving along with lesson 18 of the Linux Up Skill Challenge. This lesson is titled “Log rotation” which will be great to touch on Linux logs as they are not something I have very much experience with.

The lesson starts with talking about logrotate and how helpful it can be with managing and automating your logs. That sounds wonderful to me! The lesson has me check the logs on my server and see that they are already being rotated:

david@linux-up-skill:~# ls /var/log/ alternatives.log dmesg.1.gz syslog alternatives.log.1 dmesg.2.gz syslog.1 alternatives.log.2.gz dpkg.log syslog.2.gz apache2 dpkg.log.1 syslog.3.gz apt dpkg.log.2.gz syslog.4.gz auth.log faillog syslog.5.gz auth.log.1 installer syslog.6.gz auth.log.2.gz journal syslog.7.gz auth.log.3.gz kern.log ubuntu-advantage.log auth.log.4.gz kern.log.1 ubuntu-advantage-timer.log bootstrap.log kern.log.2.gz ubuntu-advantage-timer.log.1 btmp kern.log.3.gz ubuntu-advantage-timer.log.2.gz btmp.1 kern.log.4.gz ufw.log cloud-init.log landscape ufw.log.1 cloud-init-output.log lastlog ufw.log.2.gz dist-upgrade netserver.debug_1905 ufw.log.3.gz dmesg netserver.debug_824 unattended-upgrades dmesg.0 private wtmp david@linux-up-skill:~# ls /var/log/apache2/ access.log error.log.11.gz error.log.3.gz error.log.8.gz access.log.1 error.log.12.gz error.log.4.gz error.log.9.gz error.log error.log.13.gz error.log.5.gz other_vhosts_access.log error.log.1 error.log.14.gz error.log.6.gz error.log.10.gz error.log.2.gz error.log.7.gz

Fantastic. But when is this being done? How do you configure this? The lesson has me covered as it wants me to check on my cron scripts to find one for logrotate. OK. If I go to /etc/cron.daily I can in fact see the logrotate script there. When I look at the script I can see it is pointing to /etc/logrotate.conf for the actual configuration. If I read this file I can see logs are being rotated weekly and 4 weeks worth of logs are stored. I also see that packages log rotation information is stored in /etc/logrotate.d.

Looking in this folder I see a number of files. The lesson has me look at apache2:

/var/log/apache2/*.log { daily missingok rotate 14 compress delaycompress notifempty create 640 root adm sharedscripts postrotate if invoke-rc.d apache2 status > /dev/null 2>&1; then \ invoke-rc.d apache2 reload > /dev/null 2>&1; \ fi; endscript prerotate if [ -d /etc/logrotate.d/httpd-prerotate ]; then \ run-parts /etc/logrotate.d/httpd-prerotate; \ fi; \ endscript }

This is pretty straight forward to read and understand. The lesson ends by having me make some changes to the apache2 configuration. I end up leaving the rotation set to daily but change it to save 52 copies. The lesson gives a few links which I am going to add here for my reference into the future. The Ultimate Logrotate Command Tutorial. Use logrotate to Manage Log Files.