pfSense

Under pfSense CE 2.50, with an active OpenVPN tunnel to my ISP's VPN, unplugging the WAN cable crashes the OpenVPN client, which then fails to restart, leaving the VPN dead until I manually restart it. The crash occurs about ~1 min after disconnecting the cable, and is completely reproducible.

The OpenVPN log contains the relevant lines

Aug 27 hh:mm:ss openvpn 48798 Exiting due to fatal error
Aug 27 hh:mm:ss openvpn 48798 TCP/UDP: Socket bind failed on local address [AF_INET]aaa.bbb.ccc.ddd:0: Can't assign requested address (errno=49)

where "aaa.bbb.ccc.ddd" is the former IP address of the WAN interface (WAN gets its IP via DHCP). Before OpenVPN crashes, the system/general log contains ~50 repeated messages of the form:

arpresolve: can't allocate llinfo for aaa.bbb.ccc.ddd on igb0

where igb0 is the WAN interface.

Manually restarting the relevant OpenVPN client works, but obviously that's not a good solution.

Installing Service Watchdog, and configuring it to watch the relevant OpenVPN client instance, appears to work. Probably this should be the default?