Stuck extensions as busy

[agentsmithitaly]

Hi to all,
I'm a sysadmin in a company where we are evaluating 3CX as PBX replacement.

Two users were on an internal call when there was a brief Internet outage (3CX is on a AWS instance)
When connection resumed, everybody was available again except the two users, which were stuck as busy.
These users could place calls, but couldn't be called - they were diverted to voicemail.

I checked Activity log and reason for diverting to voicemail was that the called extension was busy.
I asked to reboot and reprovision the phone to no avail.

Finally, I restarted 3CX SIP server and in a matter of seconds the problem solved.
Unfortunately the relevant activity log seems to be lost with the restart.

Why this happens? Is there a more graceful way of fixing or preventing this than restarting server?
This is very similar to what is described on this 10 years old post https://www.3cx.com/community/threads/what-to-do-when-an-extension-is-stuck.3792/

Thank you
Nick

 

[YiannisH_3CX]

Hello @agentsmithitaly

When internet connection is lost while an extension is on a call then that call is not properly terminated because no Bye message was received by the PBX or the phone. This could result in a "stuck" call. Did you check the active calls page on the dashboard to see if you could terminate the calls from there? Where the calls visible in the switchboard?

You mentioned this was an internal call, but you did not mention what devices are being used,how the devices where provisioned or if these are 3CX clients. Do you have a VPN? An SBC? Do you have recordings enabled or PBX delivers audio?

 

[agentsmithitaly]

Dear Yannis,
Thank you for your quick reply. I'm still exploring all the myriad features it has, but I think I got the basics right.
Sorry, I didn't check the active calls page, I will pay attention to it if it happens again.
Is the switchboard you are referring the one in the Web Client?

Both extensions are 3CX clients running on Android phones (Honor 6a and Moto C Plus)
No VPN and no SBC, No recordings (PBX edition license) and no PBX delivers audio.

I wonder if there is a way to auto recover if Bye message is not received, i.e. timeout?

 

[YiannisH_3CX]

Is the switchboard you are referring the one in the Web Client?

You can use either the web client or the switchboard on a 3CX client for windows or Mac.

I wonder if there is a way to auto recover if Bye message is not received, i.e. timeout?

There is but that depends on the max duration allowed for a call set which is set to 3 hours. The call will drop after 3 hours if no BYE message is received.

 

[agentsmithitaly]

Thank you for your reply. I think an acceptable limit for a call could be 1 hour. Where is the max duration allowed parameter?

 

[jimbo59]

My linux with ssd drive reboots in under 1 minute so when I get jammed calls I just reboot.

 

[YiannisH_3CX]

@agentsmithitaly

Please note that the parameter is located under Settings / Parameters. Search for MAXCALLDURATION. The default value is set to 10800 (seconds). this value affects all calls within the PBX so if an agent is on a call for an hour the call will be dropped by the PBX.
The same applies if you set the value too high. It there is a stuck call, the call will not be dropped until the call reaches the set time. So proceed accordingly

 

[agentsmithitaly]

Thank you Yiannis, the boss agreed a maximum 45 minutes call will be enough, so I changed the parameter to 2700.

 

[Vali_3CX]

That's 3 hours Yiannish

My guess is that Yannis was referring @agentsmithitaly request (#5), since he (Yannis) mentioned a bit earlier (#4) "[...] max duration allowed for a call set which is set to 3 hours. The call will drop after 3 hours if no BYE message is received."