SBC appears as offline

[romkus]

Since over 2 weeks an SBC appears as "down" without any action from our side. The logs on SBC itself show nothing. The logs on the server show Couldn't find SBC by name '18a71bd5a0cf527aa305a130d52de772', looking up legacy by id 'sbc.c18d0465.18a71bd5a0cf527aa305a130d52de772' when restarting SBC (unclear if this is just a warning). The end devices are still working.

How can we troubleshoot this and what is happening?

 

[Alphabetic]

Have you restricted the presence port on the firewall of where your PBX sits?

• Port 443 or 5001 (inbound, TCP) HTTPS for Presence and Provisioning, or the custom HTTPS port you specified.

 

[romkus]

No ports are restricted, and 443 can be reached. The logs on the PBX (even advanced) do now show anything.

 

[TheodorosG_3CX]

Has there been any change from the SBC side?

 

[romkus]

No changes, neither on the SBC side nor on the PBX side.

 

[TheodorosG_3CX]

You need to check the tunnel log from the PBX side at that time. What is the error in this log?

 

[romkus]

As I said, there are no errors logged in at the SBC...

 

[TheodorosG_3CX]

This log is from the PBX side. Have you checked also the PBX side?

 

[romkus]

Yes, PBX logs "The logs on the server show Couldn't find SBC by name..." and SBC does not log anything, except not finding a tunnel SRV record.

 

[TheodorosG_3CX]

This might require further investigation with captures and logs to determine the cause. I would suggest that you create a ticket to the Technical Support.