CHANUNAVAIL issue at outgoing

Asterisk Asterisk SIP
1

What is the solution?
System: I am running raw Asterisk 13 on ubuntu Server for test purpose. Incoming is ok but Outbound is showing the following log.
Getting this log during outbound call:

== Using SIP RTP CoS mark 5
– Executing [01907455095@phones:1] Dial(“SIP/321-0000000e”, “SIP/provider/01907455095”) in new stack
== Using SIP RTP CoS mark 5
– Called SIP/provider/01907455095
– SIP/provider-0000000f is making progress passing it to SIP/321-0000000e
– SIP/provider-0000000f is making progress passing it to SIP/321-0000000e
– SIP/provider-0000000f is making progress passing it to SIP/321-0000000e
[May 16 12:02:27] WARNING[1261][C-00000009]: chan_sip.c:24048 handle_response_invite: Received response: “Forbidden” from ‘“321” sip:321@sip.icctalk.com;tag=as4a3889ff’
== Everyone is busy/congested at this time (1:0/0/1)
– Auto fallthrough, channel ‘SIP/321-0000000e’ status is ‘CHANUNAVAIL’

2

The remote side sent back a Forbidden response. Why that specifically is you would need to ask them, but you could also provide the SIP trace (sip set debug on) and configuration minus passwords. Since they sent back a 183 Session Progress though I think you’ll need to talk to them.

3

As a general principle, it is the first error or warning that is the most useful.