#!/bin/bash

SLEEPTIME=60

while :; do
    VAR=$(asterisk -rnx "iax2 show peers" | grep --binary-files=text "192.168." | wc -l)
    sleep $SLEEPTIME
done


./test.sh &
[1] 28301
#

[1]+  Stopped                 ./test.sh
#

ps aux:
root     28301  0.0  0.0   3616  1224 pts/7    T    21:40   0:00 /bin/bash ./test.sh
root     28302  0.0  0.0   3616  1228 pts/7    T    21:40   0:00 /bin/bash ./test.sh
root     28303  0.0  0.0   4080  1492 pts/7    T    21:40   0:00 asterisk -rnx iax2 show peers
root     28304  0.0  0.0   2756   624 pts/7    T    21:40   0:00 grep --binary-files=text 192.168.
root     28305  0.0  0.0   2700   500 pts/7    T    21:40   0:00 wc -l