Queue Outgoing Call and route to mobile Dongle Trunk when free

We got 10 lines out mainly for mobile and we had around 300 users. We are using Asterisk 1.8 and each customer will have their own asterisk extension. The line out is actually a mobile dongle with sim card. We create custom trunk for each mobile dongle with the syntax Custom Dial String: Dongle/dongle0/$OUTNUM$

They normally experience the busy tone when calling out when all the lines have been used as we only have 10 lines out and we do not implement Queue yet

I just wonder if we can queue these incoming calls and once one of outgoing line is free, this incoming call can connect to this free one?

I just do not know how Asterisk queue can keep track of the mobile dongle trunk.

No, you can’t queue incoming calls. The caller will always see the line as busy until it isn’t.

Please only post once the same question, and please post in relevant forum.

thanks but this is I think a very basic feature of any PBX system should have. I have googled and found the way is to use Custom Destination and Misc Application to cheat Queue to think the Trunk is static agent

Certainly answer no would be an very easy and obvious answer but as asterisk is the open platform, we should be able to tweak it the way we want

You miss the point, a busy fxo (pstn line, including cell phones) is always busy when it is busy, there is NO way to queue up incoming calls, that’s just the way it works. Your only option is to get more lines.

(if you are talking about outbound, then look into camp-on)