How to configure chan_pjsip to send NOTIFY/SIPFrag messages on receiving REFER message

Hello All,

I am looking for a procedure of how to send NOTIFY/SIPFrag messages on receiving REFER requests for call transfer scenarios. Basically I want to simulate following kind of flow:

Currently, on receiving REFER, asterisk sends only a single NOTIFY with Subscription-State: terminated;reason=noresource.
Is there any configuration on an asterisk that enables NOTIFY/SIPFrag as per RFC3515 Section 4.1 https://datatracker.ietf.org/doc/html/rfc3515#section-4.1?

Thanks
Rohit

Are you, by any chance, hanging up the channel that issued the REFER? I’m pretty sure that chan_sip supported this, providing you didn’t send BYE on the referring channel, so I’d be surprised if chan_pjsip didn’t.