;
; randomize pstn gw
;
exten => _XX.,1,SetVar(NUMERO=${EXTEN})
exten => _XX.,2,Random(50:pstngw-1,1)
exten => _XX.,3,Goto(default,1)
                                                                                                                             
exten => pstngw-1,1,Dial(IAX2/${EXTEN}/${NUMERO}@pstn)
exten => pstngw-1,2,Hangup
exten => pstngw-1,202,Goto(default,1) ; exten +202 if qualify fails gw check
                                                                                                                             
exten => pstngw-2,1,Dial(IAX2/${EXTEN}/${NUMERO}@pstn)
exten => pstngw-2,2,Hangup
exten => pstngw-2,202,Goto(default,1)
                                                                                                                             
;
; if we're on default, be sure to go in reverse order
; Also we get something if one box is down
;
exten => default,1,Dial(IAX2/pstngw-2/${NUMERO}@pstn)
exten => default,2,Dial(IAX2/pstngw-1/${NUMERO}@pstn)
exten => default,3,Hangup