Incoming Calls rejected by SIP 486 Busy Message (Disabled by Forwarding Rule)

[Kwang Mien]

Hi,

I am getting intermittent incoming call issues. 3CX server is version 18 Update 4 (Build 965). The network setup is as follows :


DID Provider -> Our Server -> 3CX -> IP Phones

When DID is called, our server will route the call to 3CX. 3CX server will ring the IP Phones. During the ringing phase, there are times when 3CX would reject
the call with a SIP 486 Busy message. When I check in the Busy message, it showed " Warning : 499 teelai.midtown.com "Disabled By Forwarding Rule"

May I know what could be the issue ? and what does Disabled By Forwarding Rule in the SIP 486 signify ?

Thanks.

 

[Evolute IT]

Are you using the IP Phones call forwarding feature? If so, that is not supported and will cause this kind of errors.

 

[neo]

Hi,

I am getting intermittent incoming call issues. 3CX server is version 18 Update 4 (Build 965). The network setup is as follows :


DID Provider -> Our Server -> 3CX -> IP Phones

When DID is called, our server will route the call to 3CX. 3CX server will ring the IP Phones. During the ringing phase, there are times when 3CX would reject
the call with a SIP 486 Busy message. When I check in the Busy message, it showed " Warning : 499 teelai.midtown.com "Disabled By Forwarding Rule"

May I know what could be the issue ? and what does Disabled By Forwarding Rule in the SIP 486 signify ?

Thanks.

Hi Kwang Mien,

In case your issue has not been resolved yet, I would like to point out that I encountered the same issue on v18 Update 5 (Build 418). My user was logged in a Queue but no calls was routed to the latter even though the Windows app was up and running.
On the Dashboard the latter was not there but does appear online (Green) on the users page of the console and the icon Q was active on the app status bar.
Internal calls were fine but from external callers, the user's extension was unreachable and the call just dropped - no voicemail or whatsoever.
PCAP traces showed a 486 Busy Here and inside the Message Header of the traces, the Warning: 499 .... "Disabled by Forwarding Rule" was shown.
I even requested to uninstall the Android app and Shutdown Windows but the status on the console remained Online and all test calls again just dropped - no voicemail triggered.

Over an hour of investigation, I finally reset the user's credentials and eventually the status on the console for this extension turned red! And re-provision the Windows app which instantly go back to Green on the Console but still logged out from the Dashboard .
Then, from the user's extension page, on the General tab, I noticed that the user's DID did not appear there even it was already created in the SIP Trunks - DID section. I deleted it and re-create it and re-assign it.
Inbound Rule checked, no issue.
Now Inbound calls from external numbers were fine again.

Hope this can help anyone out there facing same issue.