Currently, there's no way to restart the tasks of a service without making an actual change to the service. This leads to us giving awkward workarounds as in https://github.com/docker/docker.github.io/pull/178/files, where we tell people to scale a service up and down to restore balance, or make unnecessary changes to trigger a restart. This change adds a --force option to "docker service update", which forces the service to be updated even if no changes require that. Since rolling update parameters are respected, the user can use "docker service --force" to do a rolling restart. For example, the following is supported: docker service update --force --update-parallelism 2 \ --update-delay 5s myservice Since the default value of --update-parallelism is 1, the default behavior is to restart the service one task at a time. Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
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title, description, keywords
| title | description | keywords | |
|---|---|---|---|
| service update | The service update command description and usage |
|
service update
Usage: docker service update [OPTIONS] SERVICE
Update a service
Options:
--args string Service command args
--constraint-add value Add or update placement constraints (default [])
--constraint-rm value Remove a constraint (default [])
--container-label-add value Add or update container labels (default [])
--container-label-rm value Remove a container label by its key (default [])
--endpoint-mode string Endpoint mode (vip or dnsrr)
--env-add value Add or update environment variables (default [])
--env-rm value Remove an environment variable (default [])
--force Force update even if no changes require it
--group-add value Add additional user groups to the container (default [])
--group-rm value Remove previously added user groups from the container (default [])
--help Print usage
--image string Service image tag
--label-add value Add or update service labels (default [])
--label-rm value Remove a label by its key (default [])
--limit-cpu value Limit CPUs (default 0.000)
--limit-memory value Limit Memory (default 0 B)
--log-driver string Logging driver for service
--log-opt value Logging driver options (default [])
--mount-add value Add or update a mount on a service
--mount-rm value Remove a mount by its target path (default [])
--name string Service name
--publish-add value Add or update a published port (default [])
--publish-rm value Remove a published port by its target port (default [])
--replicas value Number of tasks (default none)
--reserve-cpu value Reserve CPUs (default 0.000)
--reserve-memory value Reserve Memory (default 0 B)
--restart-condition string Restart when condition is met (none, on-failure, or any)
--restart-delay value Delay between restart attempts (default none)
--restart-max-attempts value Maximum number of restarts before giving up (default none)
--restart-window value Window used to evaluate the restart policy (default none)
--rollback Rollback to previous specification
--stop-grace-period value Time to wait before force killing a container (default none)
--update-delay duration Delay between updates
--update-failure-action string Action on update failure (pause|continue) (default "pause")
--update-max-failure-ratio value Failure rate to tolerate during an update
--update-monitor duration Duration after each task update to monitor for failure (default 0s)
--update-parallelism uint Maximum number of tasks updated simultaneously (0 to update all at once) (default 1)
-u, --user string Username or UID (format: <name|uid>[:<group|gid>])
--with-registry-auth Send registry authentication details to Swarm agents
-w, --workdir string Working directory inside the container
Updates a service as described by the specified parameters. This command has to be run targeting a manager node.
The parameters are the same as docker service create. Please look at the description there
for further information.
Normally, updating a service will only cause the service's tasks to be replaced with new ones if a change to the
service requires recreating the tasks for it to take effect. For example, only changing the
--update-parallelism setting will not recreate the tasks, because the individual tasks are not affected by this
setting. However, the --force flag will cause the tasks to be recreated anyway. This can be used to perform a
rolling restart without any changes to the service parameters.
Examples
Update a service
$ docker service update --limit-cpu 2 redis
Perform a rolling restart with no parameter changes
$ docker service update --force --update-parallelism 1 --update-delay 30s redis
In this example, the --force flag causes the service's tasks to be shut down
and replaced with new ones even though none of the other parameters would
normally cause that to happen. The --update-parallelism 1 setting ensures
that only one task is replaced at a time (this is the default behavior). The
--update-delay 30s setting introduces a 30 second delay between tasks, so
that the rolling restart happens gradually.
Adding and removing mounts
Use the --mount-add or --mount-rm options add or remove a service's bind-mounts
or volumes.
The following example creates a service which mounts the test-data volume to
/somewhere. The next step updates the service to also mount the other-volume
volume to /somewhere-elsevolume, The last step unmounts the /somewhere mount
point, effectively removing the test-data volume. Each command returns the
service name.
-
The
--mount-addflag takes the same parameters as the--mountflag onservice create. Refer to the volumes and bind-mounts section in theservice createreference for details. -
The
--mount-rmflag takes thetargetpath of the mount.
$ docker service create \
--name=myservice \
--mount \
type=volume,source=test-data,target=/somewhere \
nginx:alpine \
myservice
myservice
$ docker service update \
--mount-add \
type=volume,source=other-volume,target=/somewhere-else \
myservice
myservice
$ docker service update --mount-rm /somewhere myservice
myservice