Call Forward All with linksys phone not updating CUCM line setting.

[rajesh.kumar]

Hi

We have CUCM 9.1.2 and there are mix of Cisco and linksys phones.

When I enter Call Forward All on Cisco IP phone, CFA number is updated on CUCM phone line configuration.

But when I do Call Forward All on Linksys SPA942/SPA962 phones, CFA number is not updating on CUCM phone line configuration.

Any feedback ?

Rgds

Rajesh Kumar

[Nadeem Ahmed]

Have you added this linksys phone like a third party sip device ?

Br,
Nadeem 

Please rate all useful post.

[rajesh.kumar]

yes, added as third-party sip advanced.

Rgds

Rajesh

[Jonathan Schulenberg · Accepted solution]

I can't find documentation to prove this but I believe this won't work the way you want. The mechanism that Cisco IP phones use to communicate CFA information is a proprietary SIP extension, which is blocked on third-party SIP device types. In other words, RFC3261 doesn't provide a mechanism to do this. Most likely, the way the phone deals with CFA is to issue a REFER when it receives the INVITE from CUCM. The easiest way to be sure is to just grab a packet capture of both the user enabling CFA and an incoming call while it's on. If it does in fact use REFER, you need to set the Rerouting Calling Search Space on the device in CUCM to a CSS that includes whatever destinations CFA should be allowed to reach.

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