ping IP

[from-internal-custom]
exten => *37,1,set(tower_1=10.0.0.200)
exten => *37,n,set(ping=${SHELL(ping -c 1 ${tower_1} | grep ttl= | wc -l)})
exten => *37,n,verbose(${ping:0:1})
exten => *37,n,gotoif($["${ping:0:1}" = "1"]?online:offline)
same=>n(online),Playback(demo-thanks)
same=>n,hangup()
same=>n(offline),Playback(im-sorry)
same=>n,hangup()