read -r -p "SIP Peer name (e.g. ATAx1): " peer
status=`sudo asterisk -rx 'sip show peer $peer' | grep -i "status"`

SIP Peer name (e.g. ATAx1): ATAx1
SIP Peer status for ATAx1:
Press ENTER to return:

status=`sudo asterisk -rx 'sip show peer ATAx1' | grep -i "status"`

SIP Peer name (e.g. ATAx1): ATAx1
SIP Peer status for ATAx1:   Status       : UNKNOWN