This is my first bash script using some resources I found online. I think there is a better way to write this perhaps using some other form of conditionals (if then vs control operators).
It is a script that basically checks if a host is up or down (check if it is ping-able). You dump all the ip addresses you want into a file, then run the script calling on the file. The text file looks like this:
8.8.8.8
4.8.8.8
4.4.4.4
127.0.0.1
The actual script looks like this. Is the 2>&1 necessary because it worked without. I had to play around with the brackets a lot.
#!/bin/bash
while read line
do
A=$(ping -c 1 $line)
((echo $A | grep "64 bytes") > /dev/null 2>&1 && (echo "UP - "$line)) || echo "DOWN - "$line
done < $1
Thank you!
You can do it entirely without brackets:
while read -r address; do
ping -c 1 $address >/dev/null 2>&1 && echo "UP - $address" || echo "DOWN - $address"
done < file
The >/dev/null 2>&1 redirects both STDOUT and STDERR to /dev/null meaning that whatever ping outputs won't be printed to your terminal.
You can then use the && and || operators to echo a message in case of success (ping exits with 0) or failure (ping exits with >0)
You could use if..then..else if you prefer:
while read -r address; do
if ping -c 1 $address > /dev/null 2>&1; then
echo "UP - $address"
else
echo "DOWN - $address"
fi
done < file