I’ve set the BIOS on the new server to resume running after a power failure. The OS happily comes back no problem, and docker even\u00a0starts up – but none of the containers.<\/p>\n
Apparently in docker 1.2 there is now support to restart your containers after boot<\/a>, this sounds useful, but\u00a0the version of docker in Ubuntu 16.04 is\u00a01.12.1, close but not quite recent enough.<\/p>\n No worries, we can use systemd to sort this out. The docker documentation has some examples, but I found an article<\/a> which takes a slightly different approach – one they claim is more aligned to CoreOS.<\/p>\n Adding our own services to systemd is simply a matter of adding a file to \/etc\/systemd\/system\/. The very first one I want to add is one to host my own registry. Now you probably don’t want to host your own registry<\/a> since you could simply use the public dockerhub<\/a>, or any number of other solutions. However, I’m also the type of person who hosts their own email, so of course I’m going to host my own registry.<\/p>\n The %n in the file is replaced with the ‘full unit name’. If we save this file as \/etc\/systemd\/system\/docker-registry.service the unit name should be docker-registry.<\/p>\n In a\u00a0simple configuration, the local docker registry will persist data as a docker volume.\u00a0I decided it was safer to map to a local file tree.<\/p>\n Once you’ve created the file \/etc\/systemd\/system\/docker-registry.service we need to reload the systemd daemon and start the service.<\/p>\n If all\u00a0has gone well, And yup, a reboot and we see the registry has started. So now we have a local registry to store our containers in, and a pattern to apply to make them services that start even after a reboot (expected or unexpected).<\/p>\n Pushing images to a local registry is covered in the documentation<\/a>. I might later want to add a certificate<\/a> to the registry, but it is not required.<\/p>\n","protected":false},"excerpt":{"rendered":" I’ve set the BIOS on the new server to resume running after a power failure. The OS happily comes back no problem, and docker even\u00a0starts up – but none of the containers. Apparently in docker 1.2 there is now support to restart your containers after boot, this sounds useful, but\u00a0the version of docker in Ubuntu … Continue reading “Server Upgrade Part 4: systemd and docker containers”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-1571","post","type-post","status-publish","format-standard","hentry","category-computing"],"_links":{"self":[{"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/posts\/1571","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/comments?post=1571"}],"version-history":[{"count":3,"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/posts\/1571\/revisions"}],"predecessor-version":[{"id":1574,"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/posts\/1571\/revisions\/1574"}],"wp:attachment":[{"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/media?parent=1571"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/categories?post=1571"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lowtek.ca\/roo\/wp-json\/wp\/v2\/tags?post=1571"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}[Unit]\r\nDescription=Private Docker Registry\r\nAfter=docker.service\r\nRequires=docker.service\r\n\r\n[Service]\r\nTimeoutStartSec=0\r\nRestart=always\r\nExecStartPre=-\/usr\/bin\/docker stop %n\r\nExecStartPre=-\/usr\/bin\/docker rm %n\r\nExecStartPre=\/usr\/bin\/docker pull registry\r\nExecStart=\/usr\/bin\/docker run -p 5000:5000 -v \/var\/lib\/registry:\/var\/lib\/registry --name %n registry\r\n\r\n[Install]\r\nWantedBy=multi-user.target<\/pre>\n
$ sudo systemctl daemon-reload\r\n$ sudo systemctl start docker-registry.service<\/pre>\n
docker ps<\/code> should show us the new running registry (it does). Now let’s make it start every boot.<\/p>\n$ sudo systemctl enable docker-registry.service<\/pre>\n