It may happen that remote SIP phones are registered on PBXware but appear offline.
You will then need to check the following points:
In extensions :
- UAD Location: Remote
- NAT: Yes
In the phone settings:
- Pass the value “Registration Timer” to 120 seconds
- Enable Keep Alive with a reduced interval.
Snom case:
In the WEB interface of the SNOM > Identity > NAT > Interval for keepalive > Fill in 15 and set the option Offer ICE on OFF
Yealink case:
In the web interface of theYealink Accounts > Advanced and;
- Keep Alive Type: defaut
- Keep Alive Interval (Seconds): 15
If the problem persists:
- Set the SIP transport in the phone to TCP instead of UDP.
For remote phones and phones behind a router/firewall:
- The lifetime of UDP sessions (Time/Timeout/NAT Session) must be greater than or equal to 180 seconds.
- The SIP ALG feature must be disabled on active equipment (if possible)
- Outgoing traffic must be allowed.
- For the SIP protocol: traffic must be allowed to go out on ports 5060 and 5061
- The port range 10000 to 20000 in UDP must also be opened outbound on the (RTP ports, sound range).