hi ,
today I use a Gsm modem to notify zabbix alerts by sms , the organization that I work there have billionton GSM Modem:

for using this device , we must do this:
First find my usb that used by dmesg command. my used usb is /dev/ttyUSB0.
Edit sms media type :Administratopn->Media Type

change media for user in Administrations->Users

Finally add a action like this Post: Script media


NOW , if you have an error like this : error in open(/dev/ttyUSB0) [13] permission denied

you must do this is terminal : chmod 777 /dev/ttyUSB0
Enjoy your life!!