diff --git a/docs/installation/fedora.md b/docs/installation/fedora.md index eb8176296b..b1bdb19cb2 100644 --- a/docs/installation/fedora.md +++ b/docs/installation/fedora.md @@ -206,6 +206,24 @@ If you need to add an HTTP Proxy, set a different directory or partition for the Docker runtime files, or make other customizations, read our Systemd article to learn how to [customize your Systemd Docker daemon options](/articles/systemd/). +## Running Docker with a manually-defined network + +If you manually configure your network using `systemd-network` with `systemd` version 219 or higher, containers you start with Docker may be unable to access your network. +Beginning with version 220, the forwarding setting for a given network (`net.ipv4.conf..forwarding`) defaults to *off*. This setting prevents IP forwarding. It also conflicts with Docker which enables the `net.ipv4.conf.all.forwarding` setting within a container. + +To work around this, edit the `.network` file in +`/usr/lib/systemd/network/` on your Docker host (ex: `/usr/lib/systemd/network/80-container-host0.network`) add the following block: + +``` +[Network] +... +IPForward=kernel +# OR +IPForward=true +... +``` + +This configuration allows IP forwarding from the container as expected. ## Uninstall