I wonder whether others have noticed/seen this behavior, and I'm not entirely sure it will reproduce, but... I had a VPN client running for a while, not having any issues for a week, and then I noticed every 2 hours (+ a minute or two) I'd get this logged:
Dec 27 17:16:49 openvpn[11452]: TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
Dec 27 17:16:49 openvpn[11452]: TLS Error: TLS handshake failed
and around that time, attempts to use the VPN would be hung (as expected) and would come back to life on their own a bit later, only to be interrupted again a couple hours further down the road. Restarting the VPN client didn't solve the problem, as the errors came back, over and over, every two hours. Rebooting the router did clear the problem and the VPN has been solid for over a day. Now to wait and see if the problem comes back again 7 days later.
Any other debug info I should collect before/after (assuming it happens again) that would help track down the cause of the problem?
Thanks,
-Eric