docker-registry-systemd

docker registry systemd unit file

setup the docker to use the private registry mirror (coreos as an example)

• touch /run/flannel_docker_opts.env
• add DOCKER_OPTS="--registry-mirror=http://<registry ip>:<registry port> --insecure-registry=<registry ip>:<registry port>"
• note: need to add --insecure-registry if you run the registry without https and you want to push image into this private registry
• note: must use "=" for --insecure-registry. the offical website missed it.

run the registry container in systemd unit

• the unit shall be put under /etc/systemd/system/
• it is better to attach a volume to VM (for example in openstack), then the images can be saved after VM dies. you need to mount this volume to container with -v <your volume path>:/tmp/
• if you run the docker/container behind the proxy, you need to set the proxy environment for the registry contianer othewise it can't get the images from the registry-1.docker.io
• if you need to push the image to it, you need to set the environment STANDALONE=true
• if you need to use it as mirror, you have to set the environment MIRROR_SOURCEE=https://registry-1.docker.io and MIRROR_SOURCE_INDEX=https://index.docker.io when set STANDALONE=true
• in production environment with files, set environment SETTINGS_FLAVOR=local
• note: current only the registry v0.9.1 supports mirror. registry v2.0 can't support mirror but private registry now. maybe registry 2.1/docker 1.7 will support mirror.

configure docker with proxy (optional)

• touch http-proxy.conf in /etc/systemd/system/docker.service.d
• add below content

[Service]
Environment="HTTP_PROXY=http://<proxy ip>:<proxy port>" "HTTPS_PROXY=http://<proxy ip>:<proxy port>" "NO_PROXY=127.0.0.1,localhost,<registry ip>,/var/run/docker.sock" `

• note: Only can set one Environment
• note: NO_PROXY only can support full ip. it can't support ip with widecast

add volume for coreos under openstack(optinal)

• in openstact web console, create a volume
• in the controller node, use nova command to attach the volume to coreso vm: nova volume-attach <vm id> <volume id> [device name]. note: default device name is /dev/vdb
• in coreos, format the volume: mkfs.ext4 /dev/vdb
• mount the volume with systemd unit
• note: the unit name must be .mount. the subdir in the full path is connected with -. For exmaple, the full path name is /mirror/registry, then the unit name is mirror-registry.mount
• the unit shall be put under /etc/systemd/system/