github.com/itscaro/cli@v0.0.0-20190705081621-c9db0fe93829/docs/reference/commandline/update.md (about) 1 --- 2 title: "update" 3 description: "The update command description and usage" 4 keywords: "resources, update, dynamically" 5 --- 6 7 <!-- This file is maintained within the docker/cli GitHub 8 repository at https://github.com/docker/cli/. Make all 9 pull requests against that repo. If you see this file in 10 another repository, consider it read-only there, as it will 11 periodically be overwritten by the definitive file. Pull 12 requests which include edits to this file in other repositories 13 will be rejected. 14 --> 15 16 ## update 17 18 ```markdown 19 Usage: docker update [OPTIONS] CONTAINER [CONTAINER...] 20 21 Update configuration of one or more containers 22 23 Options: 24 --blkio-weight uint16 Block IO (relative weight), between 10 and 1000, or 0 to disable (default 0) 25 --cpu-period int Limit CPU CFS (Completely Fair Scheduler) period 26 --cpu-quota int Limit CPU CFS (Completely Fair Scheduler) quota 27 --cpu-rt-period int Limit the CPU real-time period in microseconds 28 --cpu-rt-runtime int Limit the CPU real-time runtime in microseconds 29 -c, --cpu-shares int CPU shares (relative weight) 30 --cpus decimal Number of CPUs (default 0.000) 31 --cpuset-cpus string CPUs in which to allow execution (0-3, 0,1) 32 --cpuset-mems string MEMs in which to allow execution (0-3, 0,1) 33 --help Print usage 34 --kernel-memory string Kernel memory limit 35 -m, --memory string Memory limit 36 --memory-reservation string Memory soft limit 37 --memory-swap string Swap limit equal to memory plus swap: '-1' to enable unlimited swap 38 --pids-limit int Tune container pids limit (set -1 for unlimited) 39 --restart string Restart policy to apply when a container exits 40 ``` 41 42 ## Description 43 44 The `docker update` command dynamically updates container configuration. 45 You can use this command to prevent containers from consuming too many 46 resources from their Docker host. With a single command, you can place 47 limits on a single container or on many. To specify more than one container, 48 provide space-separated list of container names or IDs. 49 50 With the exception of the `--kernel-memory` option, you can specify these 51 options on a running or a stopped container. On kernel version older than 52 4.6, you can only update `--kernel-memory` on a stopped container or on 53 a running container with kernel memory initialized. 54 55 > **Warning**: The `docker update` and `docker container update` commands are 56 > not supported for Windows containers. 57 {: .warning } 58 59 ## Examples 60 61 The following sections illustrate ways to use this command. 62 63 ### Update a container's cpu-shares 64 65 To limit a container's cpu-shares to 512, first identify the container 66 name or ID. You can use `docker ps` to find these values. You can also 67 use the ID returned from the `docker run` command. Then, do the following: 68 69 ```bash 70 $ docker update --cpu-shares 512 abebf7571666 71 ``` 72 73 ### Update a container with cpu-shares and memory 74 75 To update multiple resource configurations for multiple containers: 76 77 ```bash 78 $ docker update --cpu-shares 512 -m 300M abebf7571666 hopeful_morse 79 ``` 80 81 ### Update a container's kernel memory constraints 82 83 You can update a container's kernel memory limit using the `--kernel-memory` 84 option. On kernel version older than 4.6, this option can be updated on a 85 running container only if the container was started with `--kernel-memory`. 86 If the container was started *without* `--kernel-memory` you need to stop 87 the container before updating kernel memory. 88 89 For example, if you started a container with this command: 90 91 ```bash 92 $ docker run -dit --name test --kernel-memory 50M ubuntu bash 93 ``` 94 95 You can update kernel memory while the container is running: 96 97 ```bash 98 $ docker update --kernel-memory 80M test 99 ``` 100 101 If you started a container *without* kernel memory initialized: 102 103 ```bash 104 $ docker run -dit --name test2 --memory 300M ubuntu bash 105 ``` 106 107 Update kernel memory of running container `test2` will fail. You need to stop 108 the container before updating the `--kernel-memory` setting. The next time you 109 start it, the container uses the new value. 110 111 Kernel version newer than (include) 4.6 does not have this limitation, you 112 can use `--kernel-memory` the same way as other options. 113 114 ### Update a container's restart policy 115 116 You can change a container's restart policy on a running container. The new 117 restart policy takes effect instantly after you run `docker update` on a 118 container. 119 120 To update restart policy for one or more containers: 121 122 ```bash 123 $ docker update --restart=on-failure:3 abebf7571666 hopeful_morse 124 ``` 125 126 Note that if the container is started with "--rm" flag, you cannot update the restart 127 policy for it. The `AutoRemove` and `RestartPolicy` are mutually exclusive for the 128 container.