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dockernginxdocker-swarm

How to reload nginx run as a docker swarm service?

I have a https nginx server run as docker swarm service. After updating the certificates, how could I ask nginx to reload them?

docker service update --force seems to restart the service so clients would be interrupted?

And there is no docker service run that I can run nginx -s reload.

What should I do to reload nginx without restarting it?

Solution

  • If you want zero downtime then here is one apparoach:

    Scale nginx service to 2 then update nginx service. While updating the service, it will do one by one by default. So that user won't be seeing any downtime.

    You can control this in docker-compose.yaml file.

    services:
  nginx:
    image: REPO:TAG
    deploy:
      replicas: 2
      update_config:
        parallelism: 1
        delay: 10s
      restart_policy:
        condition: on-failure

    'parallelism: 1' will update the container one by one.