Ok, my solution (one might call it a workaround) so far (example):
- Setup a ring group 2021 with members 22,24,25 with ringtime 35 and voice mailbox on “no answer”
- Create a custom device 2027 dialing Local/2026@from-internal-custom
- added an extension 2026 to extensions_custom.conf (see below)
- inbound route going to 2027
extensions_custom:
exten => 2026,1,GotoIf($[ $["${DEVICE_STATE(SIP/24)}"="BUSY"] | $["${DEVICE_STATE(SIP/24)}"="INUSE"] | $["${DEVICE_STATE(SIP/22)}"="BUSY"] | $["${DEVICE_STATE(SIP/22)}"="INUSE"] | $["${DEVICE_STATE(SIP/25)}"="BUSY"] | $["${DEVICE_STATE(SIP/25)}"="INUSE"] ]?app-blackhole,busy,1)
same => n,Dial(Local/2021@from-internal)
The GotoIf terminates with busy if one of the phones is busy (actually, testing for “INUSE” should do the trick and allow us to use ‘&’ in order to terminate/busy only if all phones are busy?), thus for a typical application with one person and multiple phones.
So far this (surprise, surprise) seems to meet the requirements for me.
The call is routed via 2027 to 2026, the GotoIf exits to terminate/busy if the condition is met (thus, we are free to use whatever condition we’d like) and dialing the ring group if not. After ringtime, the GUI “no answer” action is triggered.
I tried to mostly use FreePBX GUI elements, that’s why the routing looks a little complicated.