docker container update

docker container update

Description

Update configuration of one or more containers

Usage

docker container update [OPTIONS] CONTAINER [CONTAINER...]

Options

Parent command

Examples

Update a container’s cpu-shares

To limit a container’s cpu-shares to 512, first identify the container name or ID. You can use docker ps to find these values. You can also use the ID returned from the docker run command. Then, do the following:

$ docker container update --cpu-shares 512 abebf7571666

Update a container with cpu-shares and memory

To update multiple resource configurations for multiple containers:

$ docker container update --cpu-shares 512 -m 300M abebf7571666 hopeful_morse

Update a container’s kernel memory constraints

You can update a container’s kernel memory limit using the –kernel-memory option. On kernel version older than 4.6, this option can be updated on a running container only if the container was started with –kernel-memory. If the container was started without –kernel-memory you need to stop the container before updating kernel memory.

For example, if you started a container with this command:

$ docker run -dit --name test --kernel-memory 50M ubuntu bash

You can update kernel memory while the container is running:

$ docker container update --kernel-memory 80M test

If you started a container without kernel memory initialized:

$ docker run -dit --name test2 --memory 300M ubuntu bash

Update kernel memory of running container test2 will fail. You need to stop the container before updating the –kernel-memory setting. The next time you start it, the container uses the new value.

Kernel version newer than (include) 4.6 does not have this limitation, you can use --kernel-memory the same way as other options.

Update a container’s restart policy

You can change a container’s restart policy on a running container. The new restart policy takes effect instantly after you run docker container update on a container.

To update restart policy for one or more containers:

$ docker container update --restart=on-failure:3 abebf7571666 hopeful_morse

Note that if the container is started with “–rm” flag, you cannot update the restart policy for it. The AutoRemove and RestartPolicy are mutually exclusive for the container.