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thaJeztah merged 1 commit into from
Sep 3, 2026
+13 −7
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engine/network: Update legacy-link deprecation #25994

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20 changes: 13 additions & 7 deletions content/manuals/engine/network/links.md
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Expand Up @@ -11,13 +11,11 @@ aliases:

> [!WARNING]
>
> The `--link` flag is a legacy feature of Docker. It may eventually
be removed. Unless you absolutely need to continue using it, we recommend that you use
user-defined networks to facilitate communication between two containers instead of using
`--link`. One feature that user-defined networks do not support that you can do
with `--link` is sharing environment variables between containers. However,
you can use other mechanisms such as volumes to share environment variables
between containers in a more controlled way.
> Links on the default `bridge` network are deprecated and scheduled for removal
> in Docker Engine 30.0. Starting with Docker Engine 29.6, Docker emits a
> deprecation warning when you create a container with these links. Links on
> non-default networks remain supported. Use user-defined networks instead of
> the legacy `--link` flag whenever possible.
>
> See [Differences between user-defined bridges and the default bridge](drivers/bridge.md#differences-between-user-defined-bridges-and-the-default-bridge)
> for some alternatives to using `--link`.
Expand Down Expand Up @@ -256,6 +254,14 @@ recipient container in two ways:

### Environment variables

> [!WARNING]
>
> Legacy-link environment variables were deprecated in Docker Engine 28.4, are
> disabled by default in Docker Engine 29.0, and are scheduled for removal in
> Docker Engine 30.0. In Docker Engine 29.x, set
> `DOCKER_KEEP_DEPRECATED_LEGACY_LINKS_ENV_VARS=1` in the `dockerd` process
> environment and restart the daemon to temporarily re-enable them.

Docker creates several environment variables when you link containers. Docker
automatically creates environment variables in the target container based on
the `--link` parameters. It also exposes all environment variables
Expand Down