busy signal after second OUTCOMING call on cucm, second incoming call is not busy

[Quzky]

We want to different busy signal state for incoming and outcoming calls.

Like this, For incoming calls, we can take 2 calling there is no problem.
But, when we are on a call, if the second call comes from outcoming (from mobile numbers), we must take busy signal.

Summarize, when we are on a call, we want to take busy signal only second outcome calls, not incoming calls.

Is it possible? Is there any configuration on CUCM for this issue?

If yes, which version of CUCM?

Thanks in advance.

[Georgios Fotiadis]

If I understand your requirement well, you would like to be able to receive 2 (or more) incoming calls at an IP phone while at same time restrict the user from being able to have 2 outgoing calls at the same time.

These features are handled by the Busy Trigger and Maximum Number of Calls at Device -> Phone -> Line configuration. In your case you would like Busy Trigger > 2 and Maximum Number of Calls = 1, which is not possible, while Maximum Number of Calls should always be greater or equal than Busy Trigger.

This will also be helpful to you: Configure Multiple Calls Per Line in Cisco CallManager.

There is a workaround to accomplish this, if you configure a 2nd DN on the phone and have set forward busy the 1st line to it. For example, if 1000 is your 1st DN on the phone, configure the above counters for 1000 to be equal to 1 and then create a 2nd DN on the same phone (i.e. 1001) and have 1000 "Cfd Busy" set to 1001.

[Jaime Valencia]

Not possible, maximum number of calls and busy trigger does not differentiate incoming and outgoing calls, they're the same thing for those parameters.