Docs: host-gateway-ip daemon option IPv4+IPv6

The host-gateway-ip daemon option now accepts two addresses, one
IPv4 and one IPv6.

Signed-off-by: Rob Murray <rob.murray@docker.com>
This commit is contained in:
Rob Murray 2024-11-11 11:57:39 +00:00
parent 917d2dc837
commit 81380b9268
1 changed files with 19 additions and 6 deletions

View File

@ -62,8 +62,8 @@ Options:
-G, --group string Group for the unix socket (default "docker")
--help Print usage
-H, --host list Daemon socket(s) to connect to
--host-gateway-ip ip IP address that the special 'host-gateway' string in --add-host resolves to.
Defaults to the IP address of the default bridge
--host-gateway-ip ip-list IP addresses that the special 'host-gateway' string in --add-host resolves to.
Defaults to the IP addresses of the default bridge
--http-proxy string HTTP proxy URL to use for outgoing traffic
--https-proxy string HTTPS proxy URL to use for outgoing traffic
--icc Enable inter-container communication (default true)
@ -837,21 +837,34 @@ For details about how to use this feature, as well as limitations, see
The Docker daemon supports a special `host-gateway` value for the `--add-host`
flag for the `docker run` and `docker build` commands. This value resolves to
the host's gateway IP and lets containers connect to services running on the
addresses on the host, so that containers can connect to services running on the
host.
By default, `host-gateway` resolves to the IP address of the default bridge.
By default, `host-gateway` resolves to the IPv4 address of the default bridge,
and its IPv6 address if it has one.
You can configure this to resolve to a different IP using the `--host-gateway-ip`
flag for the dockerd command line interface, or the `host-gateway-ip` key in
the daemon configuration file.
To supply both IPv4 and IPv6 addresses on the command line, use two
`--host-gateway-ip` options.
To supply two addresses in the daemon configuration file, include two addresses
in the JSON array, as shown below. For compatibility with older versions of the
daemon, a single IP address can also be specified in a JSON string rather than
an array.
```console
$ cat > /etc/docker/daemon.json
{ "host-gateway-ip": "192.0.2.0" }
{ "host-gateway-ip": ["192.0.2.1", "2001:db8::1111"]}
$ sudo systemctl restart docker
$ docker run -it --add-host host.docker.internal:host-gateway \
busybox ping host.docker.internal
PING host.docker.internal (192.0.2.0): 56 data bytes
PING host.docker.internal (192.0.2.1): 56 data bytes
$ docker run -it --add-host host.docker.internal:host-gateway \
busybox ping -6 host.docker.internal
PING host.docker.internal (2001:db8::1111): 56 data bytes
```
### Enable CDI devices