Inbound SIP configuration

[chillimintlabs]

Hi,

I'm trying to get inbound SIP calls into our Mitel 5000 (via an asterisk server). All the settings seem correct, however i'm getting this in the asterisk logs:

-- Goto (incoming,0161XXXXXXX,16)
    -- Executing [0161XXXXXXX@incoming:16] Dial("SIP/peer6-4e76d4-0000000f", "SIP/0161XXXXXXX@192.168.50.150")
  == Using UDPTL CoS mark 5
  == Using SIP RTP CoS mark 5
    -- Called SIP/0161XXXXXXX@192.168.50.150
    -- Got SIP response 503 "Service Unavailable" back from 192.168.50.150:5060
    -- SIP/192.168.50.150-00000010 is circuit-busy
  == Everyone is busy/congested at this time (1:0/1/0)
    -- Auto fallthrough, channel 'SIP/peer6-4e76d4-0000000f' status is 'CONGESTION'

Any help appreciated on how to diagnose the issue. It seems the Mitel is rejecting the call with 503 Service Unavailable.

Thanks

[bluewhite4]

What's the inbound routing point of the SIP trunks on the Mitel?

[chillimintlabs]

I've got a SIP Trunk Group (92003) which has day/night ring-in type set to call routing table 4, then in that table I have the DDI going to a single extension.

[bluewhite4]

What about the reverse? Making a call from the Mitel to the Asterisk?

[NTEDave]

What Bluewhite4 says and have you got the relevant licenses on the system and trunks assigned to the group?