zaping.sh

#!/bin/bash

#
# Options:
#
#   zaping.sh server [mode=avg] [count=5] [interval=0.2]
#
#       server      Server to ping, either ip or dns
#       option      operational mode (default avg)
#                     "loss" to get the percentage of lost pings in a range of pings
#                     "min" to get the minimum time in a range of pings
#                     "avg" to get the average time
#                     "max" to get the max time
#       count       How many times to ping when doing a range of pings
#       interval    Interval between pings during a range.  Must be
#               greater than 0.2 (only root can go less than 0.2)
#
#   Returns positive floating point number on success and -1 on failure
#   Maximum rtt is limited to 1s

set -o pipefail

MAXAGE=60

[ $# -eq 0 ] && exit
host="$1"
mode="avg"
count=5
interval=0.2
[ "$2" != "" ] && mode="$2"
[ "$3" != "" ] && count="$3"
[ "$4" != "" ] && interval="$4"


DATAFILE="/tmp/zaping-$host-$count-$interval"

if [ -f "$DATAFILE" ]; then
    modsecs=$(date --utc --reference="$DATAFILE" +%s)
    nowsecs=$(date +%s)
    delta=$((nowsecs-modsecs))
else
    delta=999
fi
if [ $delta -gt $MAXAGE ]; then
    wrkfile=`mktemp`
    ping -c $count -i $interval -W 1 "$host" > "$wrkfile" 2>/dev/null
    loss=`grep loss "$wrkfile" | cut -f 6 -d" " | cut -f1 -d"%" || echo -1`
    min=`grep rtt "$wrkfile" | cut -f  4 -d" " | cut -f 1 -d"/" || echo -1`
    avg=`grep rtt "$wrkfile" | cut -f  4 -d" " | cut -f 2 -d"/" || echo -1`
    max=`grep rtt "$wrkfile" | cut -f  4 -d" " | cut -f 3 -d"/" || echo -1`
    rm "$wrkfile"

    echo "loss=$loss" > "$DATAFILE"
    echo "min=$min" >> "$DATAFILE"
    echo "avg=$avg" >> "$DATAFILE"
    echo "max=$max" >> "$DATAFILE"
fi

. "$DATAFILE"

case "$mode" in
    loss) echo $loss ;;
    min) echo $min ;;
    avg) echo $avg ;;
    max) echo $max ;;
esac