Frequently Asked Questions

• Frequently Asked Questions
  • How to configure Timezone
  • How to stop Dockupdater auto update
  • How install Dockupdater without docker
  • How to remove containers after service update
  • How to use with service but without stack
  • How to use special token {stack}

How to configure Timezone

To more closely monitor dockupdater actions and for accurate log ingestion, you can change the timezone of the container from UTC by setting the TZ environment variable like so:

docker run -d --name dockupdater \
  -e TZ=America/Chicago \
  -v /var/run/docker.sock:/var/run/docker.sock \
  dockupdater/dockupdater

How to stop Dockupdater auto update

Your can add label dockupdater.disable="true" on the container or service to disable auto update.

If your run a standalone container for dockupdater:

docker run -d --name dockupdater \
  -v /var/run/docker.sock:/var/run/docker.sock \
  --label dockupdater.disable="true"
  dockupdater/dockupdater

If your run dockupdater with a stack:

version: "3.6"

services:
  dockupdater:
    image: dockupdater/dockupdater
    deploy:
      labels:
        dockupdater.disable: "true"

How install Dockupdater without docker

Dockupdater can also be installed via pip:

pip install dockupdater

And can then be invoked using the dockupdater command:

$ dockupdater –interval 300 –log-level debug

Dockupdater need Python 3.6 or up

How to remove containers after service update

By default Docker swarm keep 5 stop containers by service. You can configure that number at 0 to always remove old containers.

The update your docker swarm, run that command on a manager:

$ docker swarm update –task-history-limit=0

How to use with service but without stack

You can start a service with the command line without using stack file :

docker service create --name test1 --replicas=2 --tty=true busybox

Unfortunately that cause an issue with Dockupdater. They have 2 workarounds:

Option 1

Run Dockupdater with the option --disable-containers-check. That will disable update for standalone containers.

Option 2

Add label dockupdater.disable on the containers, this will disable update for standalone containers, but service will be updated normally.

You can add label for all containers of a service like that:

docker service create --name test1 --replicas=2 --tty=true --container-label="dockupdater.disable=true" busybox

How to use special token {stack}

When you run use services, you can use a token {stack} with the --start and --stop options.

dockupdater.yml

version: "3.6"

services:
  dockupdater:
    image: dockupdater/dockupdater
    deploy:
      placement:
        constraints:
          - node.role == manager

stack.yml

  service1:
    image: image1:${TAG}
    deploy:
      labels:
        STOPS: "{stack}_service2"
        STARTS: "{stack}_service2"

  service2:
    image: image2:${TAG}

And start all stack:

docker stack deploy -c dockupdater.yml dockupdater
TAG=latest docker stack deploy -c stack.yml test1
TAG=test1 docker stack deploy -c stack.yml test2
TAG=test2 docker stack deploy -c stack.yml test3

On update of image1 this will restart service2, but only on the same stack of the image1 update.