From 6bd15a68cf59043e05bd69fccbafcfed25d7c22e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Oriol=20Franc=C3=A8s?= Date: Sun, 26 Jul 2015 10:10:42 +0200 Subject: [PATCH] Add arch install docs warning about systemd-network MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Oriol Francès --- docs/installation/archlinux.md | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/docs/installation/archlinux.md b/docs/installation/archlinux.md index 1a28c5b1aa..b18be6c371 100644 --- a/docs/installation/archlinux.md +++ b/docs/installation/archlinux.md @@ -83,3 +83,26 @@ and volumes run the following command: $ rm -rf /var/lib/docker You must delete the user created configuration files manually. + +## Issues + +### systemd-network + +Users of systemd-network >= v220 who have configured their network manually by +creating an `.network` file in `/etc/systemd/network/` may have to add +the following line to make sure IP Forwarding is not disabled: + +``` +[Network] +... +IPForward=kernel +... +``` + +From systemd-network v220 onwards, the forwarding setting for a given network +defaults to *off* (instead of not being set). This prevents IP Forwarding to +happen, since docker only enables `net.ipv4.conf.all.forwarding` (which is +overriden by `net.ipv4.conf..forwarding` being disabled) + +Adding `IPForward=kernel` to the `.network` file prevents this +behavior, allowing IP Forwarding to function as expected.