Proxmox shutdown at startup script

#!/bin/sh

# CONFIGURABLE
URI="some.real.url"
FILENAME="pme.txt"
DST_DIR=/tmp
PWROFF_DELAY=1
LOG_FILE=/var/log/checkpwr.log

# GENERATED
FULL_PATH_FILE=${DST_DIR}/${FILENAME}
FULL_URI="${URI}/${FILENAME}"

if [ -f $LOG_FILE ]; then
    touch $LOG_FILE
fi

if [ -f $FULL_PATH_FILE ]; then
    rm -f $FULL_PATH_FILE
fi
if [ -f $FULL_PATH_FILE ]; then
    echo "CRITICAL: Count not remove $FULL_PATH_FILE"
    exit 1;
fi


wget $FULL_URI -P $DST_DIR
if [ ! -f $FULL_PATH_FILE ]; then
    echo "Couldn't retrieve $FULL_URI"
    exit 1;
fi

cat $FULL_PATH_FILE | grep -i "POWER" | grep -i "OFF"
if [ $? -eq 0 ];
then
    date >>$LOG_FILE
    echo "Performing shutdown" >>$LOG_FILE
    whoami >>$LOG_FILE
    shutdown -P $PWROFF_DELAY >>$LOG_FILE &
    echo "">>$LOG_FILE
fi