diff --git a/docs/reference/commandline/dockerd.md b/docs/reference/commandline/dockerd.md index f290045471..9a62bbf97d 100644 --- a/docs/reference/commandline/dockerd.md +++ b/docs/reference/commandline/dockerd.md @@ -46,6 +46,7 @@ Options: --default-gateway ip Container default gateway IPv4 address --default-gateway-v6 ip Container default gateway IPv6 address --default-ipc-mode string Default mode for containers ipc ("shareable" | "private") (default "private") + --default-network-opt mapmap Default network options (default map[]) --default-runtime string Default OCI runtime for containers (default "runc") --default-shm-size bytes Default shm size for containers (default 64MiB) --default-ulimit ulimit Default ulimits for containers (default []) @@ -1449,6 +1450,7 @@ This is a full example of the allowed configuration options on Linux: "default-cgroupns-mode": "private", "default-gateway": "", "default-gateway-v6": "", + "default-network-opts": {}, "default-runtime": "runc", "default-shm-size": "64M", "default-ulimits": { @@ -1566,6 +1568,7 @@ This is a full example of the allowed configuration options on Windows: "containerd-plugin-namespace": "docker-plugins", "data-root": "", "debug": true, + "default-network-opts": {}, "default-runtime": "", "default-ulimits": {}, "dns": [], @@ -1711,3 +1714,50 @@ $ sudo dockerd \ --data-root=/var/lib/docker-bootstrap \ --exec-root=/var/run/docker-bootstrap ``` + +### Default network options + +The `default-network-opts` key in the `daemon.json` configuration file, and the +equivalent `--default-network-opt` CLI flag, let you specify default values for +driver network driver options for new networks. + +The following example shows how to configure options for the `bridge` driver +using the `daemon.json` file. + +```json +{ + "default-network-opts": { + "bridge": { + "com.docker.network.bridge.host_binding_ipv4": "127.0.0.1", + "com.docker.network.bridge.mtu": "1234" + } + } +} +``` + +This example uses the `bridge` network driver. Refer to the +[bridge network driver page](https://docs.docker.com/network/drivers/bridge/#options) +for an overview of available driver options. + +After changing the configuration and restarting the daemon, new networks that +you create use these option configurations as defaults. + +```console +$ docker network create mynet +$ docker network inspect mynet --format "{{json .Options}}" +{"com.docker.network.bridge.host_binding_ipv4":"127.0.0.1","com.docker.network.bridge.mtu":"1234"} +``` + +Note that changing this daemon configuration doesn't affect pre-existing +networks. + +Using the `--default-network-opt` CLI flag is useful for testing and debugging +purposes, but you should prefer using the `daemon.json` file for persistent +daemon configuration. The CLI flag expects a value with the following format: +`driver=opt=value`, for example: + +```console +$ sudo dockerd \ + --default-network-opt bridge=com.docker.network.bridge.host_binding_ipv4=127.0.0.1 \ + --default-network-opt bridge=com.docker.network.bridge.mtu=1234 +``` diff --git a/man/dockerd.8.md b/man/dockerd.8.md index 04a185a4df..e723f8a2e8 100644 --- a/man/dockerd.8.md +++ b/man/dockerd.8.md @@ -20,6 +20,7 @@ dockerd - Enable daemon mode [**--default-gateway**[=*DEFAULT-GATEWAY*]] [**--default-gateway-v6**[=*DEFAULT-GATEWAY-V6*]] [**--default-address-pool**[=*DEFAULT-ADDRESS-POOL*]] +[**--default-network-opt**[=*DRIVER=OPT=VALUE*]] [**--default-runtime**[=*runc*]] [**--default-ipc-mode**=*MODE*] [**--default-shm-size**[=*64MiB*]] @@ -186,6 +187,9 @@ $ sudo dockerd --add-runtime runc=runc --add-runtime custom=/usr/local/bin/my-ru Example: base=172.30.0.0/16,size=24 will set the default address pools for the selected scope networks to {172.30.[0-255].0/24} +**--default-network-opt**=*DRIVER=OPT=VALUE* + Default network driver options + **--default-runtime**=*"runtime"* Set default runtime if there're more than one specified by **--add-runtime**.