Active calls on an Asterisk

Command:
watch -n 1 "sudo asterisk -vvvvvrx 'core show channels' | grep call"

Watch active calls on an Asterisk PBX

Show active calls as the happen on an Asterisk server. Note that the Asterisk command (in single quotes) is formatted for Asterisk 1.6. Use the -n flag on the watch command to modify the refresh period (in seconds - default is 2 seconds).