Hi I have a TDM card with 8 FXO port and I wanted to check a specific port if it is available so that I can transfer the call to that port.

Scenario:

An incoming calls goes to FXO port no. 1, I want to check first all ports from 2-8 if there is an available port and route the call to the available port it sees and if no available port the port no. 1 will take the call.

Can someone tell me what is the command in asterisk to check the available FXO port.

lsdahdi
Use it when there is no call, and then use it when you have any call.

Can I use that in the dialplan? I want to check it inside the dialplan

In that case investigate on DEVICE_STATE and ChanIsAvail
asterisk -rx "core show function DEVICE_STATE"
asterisk -rx "core show application ChanIsAvail"