All circuits busy on inbound.

[Two8nine]

Vicidial version: 2.14-694a
Vicidial build: 181005-1738
Asterisk version: 13.21.1-vici

Hi, I'm trying to pin down an issue we're having with inbound calls. (We are 99% outbound).

It was reported to us that sometimes when someone calls into our inbound line, they either get an immediate hangup, a fast-busy, or the message "all circuits are busy.".

My assumption is that there are more calls in place than we have lines, but didn't quite add up to me. The server report lists our peak concurrent calls as 30(outbound) and 3(inbound) for that day. We have 46 SIP trunks available.

There are no auto-dialed/predictive dialing going on, just manual calls. Right now each of our telephony servers has 'max trunks' set as 46, and 'balance dialing' set to Y. I'm not really sure how this works, should it be set to 23 each, or does this not even apply for non-predictive/auto dialing?

Lastly, we use the Canada Caller id loopback in the extensions.conf -- I understand that it increases load, but am less clear on the carrier trunk utilization, so unsure if it is affect our trunk usage.

Regards.

[williamconley]

Good job posting your Vicidial specs. It's also useful if you post your installer with version. Really.

When you purchase a DID, you either purchase one with "per minute" charges (which usually allow unlimited channels, since you are paying per minute anyway so they don't care how many you have) or you think you're getting smart by purchasing a DID with unlimited minutes. But that "unlimited minutes" usually comes with a limit of one or two channels. So your third caller will get .. a busy signal or simple hangup.

It's also possible your inbound carrier has other limitations in place, and that your SIP account settings in Vicidial for the connection you get your calls through has a channel limit. But most of the time, it's "you bought a channel-limited DID".

[teleinx]

a fast-busy, or the message "all circuits are busy." may be an indication not enough voice paths capacity on your end or your carrier. Different carriers that call into your DID may treat the failed attempt with their own message or tone.
The immediate hangup is a different issue. If the call was answered and hung up then its something else going on your end.

[williamconley]

...
The immediate hangup is a different issue. If the call was answered and hung up then its something else going on your end.

or a bad player telco who wants to charge for that first increment for fake phone calls. not nearly as pervasive as the more common FAS types, but it happens.

teleinx is correct, of course, that answer/hang up is usually a configuration issue: no matching codec is quite normal (you have g729, and they have ulaw ... no match, no sound, hangup).