Ugly but useful hack to repeatedly (at a broad interval, e.g. 10s or 30s) ping a server and log whether it replied. Does not use cron.

pingtest.sh

#!/usr/bin/env bash

## Sends a ping to a server and writes a failure or success log message 
## Logs results to syslog; find and filter in Console, search for "PINGTEST"

# Change this as needed, must be server that responds to pings
PINGDEST=192.168.1.1

# Interval in seconds to send a ping (e.g. send every X seconds)
INTERVAL=10

while :; do
    ping -t 2 -c 1 $PINGDEST 2>&1 >/dev/null
    if [ $? -eq 0 ]; then
        logger -t "PINGTEST" Ping to $PINGDEST successful
    else
        logger -t "PINGTEST" FAIL at `date` - no ping from $PINGDEST
    fi
    sleep $INTERVAL
done