I'm running into a strange issue where OpenVPN will inconsistently start dropping all traffic when running in DCO mode and using the VPN while connected on the local network, but always works in TUN mode. I haven't been able to pin down when or how it stops working, but notice it usually fails when the following appears in the log:
Failed to create interface ovpns1 (SIOCSIFNAME): File exists (errno=17)
DCO device ovpns1 already exists, won't be destroyed at shutdown
and ifconfig does not show the RUNNING flag for ovpns1. I've tried bringing the interface down before starting the server, but still get the above message.
Does anyone else have inconsistent issues when using DCO, but it otherwise works when in TUN mode?