Hi Jason,

Thanks for the very quick response.

It happens with both the August and September snapshots. Kernel 4.9.35+, Raspbian based on Debian 9 and nothing odd in dmesg.

However, your comment about network management daemons running is most interesting. Here's an extract from journalctl's output:

Sep 09 21:31:28 janus ifplugd(wg0)[6903]: ifplugd 0.28 initializing.
Sep 09 21:31:28 janus ifplugd(wg0)[6903]: Using interface wg0/00:00:00:00:00:00
Sep 09 21:31:28 janus ifplugd(wg0)[6903]: Using detection mode: IFF_RUNNING
Sep 09 21:31:28 janus ifplugd(wg0)[6903]: Initialization complete, link beat detected.
Sep 09 21:31:28 janus ifplugd(wg0)[6903]: Executing '/etc/ifplugd/ifplugd.action wg0 up'.
Sep 09 21:31:28 janus ifplugd(wg0)[6903]: client: Ignoring unknown interface wg0=wg0.
Sep 09 21:31:29 janus ifplugd(wg0)[6903]: Program executed successfully.

So, something is triggering ifplug. I'm unsure what it might be doing and it seems to imply that it's ignoring it but maybe this is the cause of the problem. wg0 is not mentioned in /etc/network/interfaces so maybe ifup is trying to be helpful? There may well be a race condition between ifup and wg-quick…

Regards,

Jim.

Hey Jim,

That's very odd indeed. Do you have any other network management
daemons running on there that could be interfering?

Also: what snapshot version, kernel version, distribution, etc are you
using? Anything odd in dmesg after running wg-quick?

Regards,
Jason