I’m getting some weird problems on our phone system over the past few days. Our IP phones becomes unregistered after couple of hours. Usually it happens every morning…. CLI show SIP/2.0 401 Unauthorized on sip debugging logs… We dont have any problems over the past few years and this problem just came up 3 days ago…
Are the phones on the same subnet as the phone system or are they remote (e.g. NATed) through a firewall?