System does not "see" a phone

I have a new install Freepbx Distro version 12. New Yealink phones, one of them is a T26 the others are T28. The T26 is literally plugged in with a 10’ patch cord direct to the PoE switch. The system is also plugged into that switch. When the phone is first booted it works fine. Sometime later, can’t determine when, the system does not acknowledge the phone is there. Looking at the Sip_info report the phone status is unreachable. I can walk up to that phone and use it for making calls, but incoming calls do not get sent to it. I have changed, patch cord, ports on the switch and I have defaulted the phone and manually set it up. What could be doing this?? None of the other 10 phones do this.

Thanks in advance for any ideas.

hi the phone its last firmaware version ?

Are you using Asterisk 11.20? If so its broken for Yealink phones. Upgrade to 11.21

With my luck Tony that is what is going on at this location. They have had one issue after another. What is the sequence to do that and can it be done on an in service system without interruption?

I haven’t gotten to that system yet, similar systems that were installed about the same time are 11.18

So I can use Asterisk-version-switch and use 11 and it will upgrade or truly upgrade to 13. I read somewhere that 13 was affected is the version 13 upgrade include the fix for this?


Just talked to a tech that is having the same problem with a Grandstream 2140 Asterisk there is 11.20 Same thing going on. The user can call out all they want but the Sip Chan info shows the phone is unreachable.