{"id":839,"date":"2022-03-31T19:18:19","date_gmt":"2022-03-31T19:18:19","guid":{"rendered":"https:\/\/www.ebnet.us\/?p=839"},"modified":"2022-04-30T23:16:01","modified_gmt":"2022-05-01T03:16:01","slug":"how-to-rotate-the-traefik-access-log-in-docker-swarm","status":"publish","type":"post","link":"https:\/\/www.ebnet.us\/index.php\/2022\/03\/31\/how-to-rotate-the-traefik-access-log-in-docker-swarm\/","title":{"rendered":"How to rotate the Traefik access.log in Docker Swarm"},"content":{"rendered":"\n

I enabled Traefik<\/strong><\/a> access logs to use in Grafana<\/a><\/strong> for a Traefik to Loki<\/a><\/strong> dashboard. I quickly found out Traefik access logs grow quickly and I would need to rotate the Traefik access.log in Docker Swarm. Since I have Traefik running in a container in Docker Swarm we will have to tell the logrotate daemon to find and a send a USR1 signal to the container. If we do not send a USR1 signal the container will stop logging when the log is rotated. While this post is focused on Traefik, the same principles should work for any container running as a Docker service writing logs to the host \/var\/log directory.<\/p>\n\n\n\n

\"Traefik-Via-Loki-Dashboard\"
Grafana Traefik Via Loki Dashboard<\/figcaption><\/figure>\n\n\n\n

Logrotate Definition for Traefik access.log<\/h2>\n\n\n\n
\/var\/log\/traefik\/access.log {\n\tdaily\n\tcompress\n\tdelaycompress\n\tpostrotate\n\tdocker kill --signal=\"USR1\" $(docker ps | grep traefik | awk '{print $1}')\n\tendscript\n}<\/code><\/pre>\n\n\n\n
The important line is the post command “docker kill –signal=”USR1″ $(docker ps | grep traefik | awk ‘{print $1}’)”<\/strong> which will find your container by its service name and send the needed USR1 signal<\/p>\n","protected":false},"excerpt":{"rendered":"
I enabled Traefik access logs to use in Grafana for a Traefik to Loki dashboard. I quickly found out Traefik access logs grow quickly and I would need to rotate the Traefik access.log in Docker Swarm. Since I have Traefik running in a container in Docker Swarm we will have to tell the logrotate daemon...<\/p>\n","protected":false},"author":1,"featured_media":843,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[12,28,25,27],"tags":[9,10,26],"class_list":["post-839","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-docker","category-linux","category-software","category-traefik","tag-docker","tag-dockerswarm","tag-traefik"],"featured_image_src":"https:\/\/www.ebnet.us\/wp-content\/uploads\/2022\/03\/Traefik-Logo.webp","author_info":{"display_name":"Ed Brandon","author_link":"https:\/\/www.ebnet.us\/index.php\/author\/bigeb\/"},"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t