Help with Asterisk: Logging attended transfers

[Ret]

I'm sorry if this post is not entirely related to Yealink phones.

I have an Elastix 2.5 server with Asterisk and FreePBX 2.11.
I'm using T19 and T26 phones with the latest 72 and 73 firmwares. They work just fine together.

I have a problem with Asterisk logs. Attended transfers performed by these phones buttons do not appear correctly.
For example: if A calls B, and B transfers (attended) that call to C
all i see in the logs is call A->B and then another for call B->C. This is not entirely correct as A was left talking to C after the transfer.
I would like the logs to show A->B and A->C. This is the way that unattended transfers appear.

I set up my phones to use PAI header and in Asterisk their SIP settings use

trustrpid=yes
sendrpid=pai

Does anyone here have a suggestion on how to fix this?
Thanks!

[Flora_Yealink]

Hello,
So your mean the phone behaves correct while the log in the Asterisk is incorrect ?
For Attended transfer call:
If A calls B, B answers the call , A and B are in the call , A tells B that A want to find C
B presses Transfer +C's number to make a call to C, C answers the Call, B then presses the Tranfer button to finish the transfer, now B back to idle states, and A and C are in the call.

in this case, you can refer to the sip follow for Yealink phones,hope it can help.
http://www.yealink.com/Upload/UCOne/2014...V73_40.pdf
Call Transfer with Consulation in the page 56

Best Regards!

[Ret]

Yes, transfers are done correctly by the phones but the logs are not entirely correct.
The reason is that transfers by phone buttons rely on pure SIP protocol they don't use Asterisk built-in version of attended transfers (*2).
In the case you mention "If A calls B, B answers the call , A and B are in the call , A tells B that A want to find C
B presses Transfer +C's number to make a call to C, C answers the Call, B then presses the Tranfer button to finish the transfer, now B back to idle states, and A and C are in the call."
My Asterisk logs show an entry showing call from A to B, and then another call (with another Source channel ID) from B to C. So we cannot infer that a call from A to C has been made.

Unattended transfer, on the other hand, show up just fine on the logs. There's an entry showing call A to B and then another entry showing a call from A to C (Showing the same source channel ID). This way we can, at least infer, that the same source channel was transferred to C.

I know this is a question more on Asterisk than on the phones, but maybe people here know have experienced the same and know the answer.
Thank you for responding!