Loop through hosts file - cat /etc/resolv.conf


 
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# 1  
Old 11-19-2011
Loop through hosts file - cat /etc/resolv.conf [SOLVED]

Quote:
SOLVED: Using -n flag on ssh line - code edited below to show working sample
Hello...

I am trying to loop through my hosts file that contains 100+ servers to check or update the nameservers on them...

My while loop is breaking after the first server responds...

Code:
#!/bin/bash 

while read line; do
	a=( $(echo $line | tr " " "\n") )
	if [ "${a[0]}" != "" ] && [ "${a[0]}" != "#" ] && [ "${a[0]}" != "127.0.0.1" ] && [ "${a[0]}" != "127.0.1.1" ]
	then
		echo "===================="
		echo ${a[0]}
		echo "===================="
		ssh -n root@${a[0]} cat /etc/resolv.conf
	elif [ "${a[1]}" == "something" ] || [ "${a[1]}" == "blah" ]
	then
		echo "End of SSHable Servers"
	exit
	fi
done < /etc/hosts

If I append an & onto the end of the ssh line - the output will loop through all servers "echo-ing" the (3) echo lines - then proceed to loop through all servers "cat-ing" out resolv.conf afterwards...

I have to be missing something easy here... I just can't put my finger on it...

Any help would be greatly appreciated...


...

Last edited by CompSCI; 11-19-2011 at 08:14 AM.. Reason: SOLVED
# 2  
Old 11-20-2011
Code:
awk '/^[0-9]/&&!/^127/{print $1}' /etc/hosts | while read line
do
    echo "===================="
    echo $line
    echo "===================="
    ssh -n root@$line cat /etc/resolv.conf
done

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