How to make callback to the hold call


I m having asterisk installed and working fine. For the inbound calls, agents are answering the call. And putting the call on hold. But after some time the agent forget that he has put the caller on hold. Is there any mechanism in asterisk by which we can make the timeout on hold calls. Or after some time asterisk makes call back, so that the agent come to know that the call is on hold and can again continue with agent ?

Agents are so busy that they forget that they put a call on hold. So, I want to resolve this by any mechanism.

Will you please give any suggestion ?

What do you mean by put the call on hold. What Asterisk calls hold is completely under the control of the holding device. Sometime people simulate hold by using parking.

When calls comes to asterisk, there is a ring group. Any one who picks the call, may put the caller on hold from the device.
After that the callee forget that he has put the call on hold.

How to give a call back in this case ? Is there any timeout setting in hold or wat ?

If we simulate hold by parking then how to continues same call after some time ?


If the devices are SIP devices, and the hold is a SIP hold (“a=sendonly”, or even RTP address =, only the SIP device can remove the hold. That’s how SIP works.

When you park a call, you specify a timeout. After that time Asterisk tries to return the call. There are some subtleties as to where it returns, which I do not remember in detail.

PS Asterisk doesn’t have “ring groups”. These are constructs, built on Asterisk primitives, that are actually created by Asterisk GUIs.

Thank you for your reply David.

You mean after the timeout, the asterisk will give the call back and connect the same channel i.e caller and callee ?


There are subtleties. I wouldn’t want to give a definitive answer off the top of my head.

As I remember it, there are two modes in which calls can be unparked. One is to device address of the parker (i.e. the channel name with the instance stripped off). The other is to the next step in the dialplan. I can’t remember the exact rules for when and how these are used.

Thank u for your help.

Let me try it out.