Setup cron job to ping computer and write result to file

Question

I'm building an interface to basically list computers on my local network that are 'alive' and more or less have a list of these nodes, and their 'status'.

I've created a file called farm_ping.sh located under /Volumes/raid/farm_scripts/_apps/_scripts/farm_ping.sh

This file contains the following, which simply pings the IP and writes it's result to a txt file also named by the given IP:

HOSTS="192.168.1.110"

# no ping request
COUNT=1

for myHost in $HOSTS
do
  count=$(ping -c $COUNT $myHost | grep 'received' | awk -F',' '{ print $2 }' | awk '{ print $1 }')
  if [ $count -eq 0 ]; then
    # 100% failed     
    echo "Host : $myHost is down (ping failed) at $(date)" > /Volumes/raid/farm_script/nodes_response/$myHost.txt
  else
    # 100% Passed
    echo "Host : $myHost is running (ping successful) at $(date)" > /Volumes/raid/farm_script/nodes_response/$myHost.txt
  fi
done

I want this to run this script every minute, here's what I have done to create a cron job:

env EDITOR=nano crontab -e

And in the cron job I wrote:

1 * * * * /Volumes/raid/farm_script/_apps/_scripts/farm_ping.sh

I saved this file, but it's been 30 mintues, and nothing has written yet, what have I done wrong?

Answer 1

Issue was cronjob syntax.

1 * * * * 

In context, * means every possible value and a number means a particular time. So this literary means the 1st minute of every hour of every day of every month of every week day.

Replacing the the 1 with a * makes it run every minute.