With a PBX at a central site I have handsets connecting from multiple remote sites over LAN-LAN VPN's. The central site running a 2860.

Since upgrading 2860's to 3.8.5_BT, and now 3.8.5.1_BT, I've seen a number of instances where the remote handset is not registered and SIP traffic appears to have stopped routing over the VPN.

For the VoIP devices affected other traffic from them was routing OK, e.g. syslog, ftp, etc. and watching the syslogs I can see the devices trying to register while the PBX syslog is not reporting any traffic from the remote devices.

This has only been observed between 2860's on newer firmware. 2820's and 2830's have not shown this issue.

Dropping and re-establishing the VPN was not sufficient to sort the problem and SIP routing has only, so far, been restored by rebooting the router.

Alan