[SOLVED] if statement to see if line is in file

keif · 09-25-2013, 06:47 AM

Good Morning,

I want to set up a script that will ssh into a host and check for a line in a file. If the line is there it prints "Yes" and if its not there it prints "No".

Here is the lines I have so far:

Code:

#!/bin/sh
for HostName in `cat /home/techs/hostlist | awk '{print $1}'`

do
        echo $HostName
        ssh root@$HostName "grep EXCENTUS_RETAIL_ID /usr1/vision/vision.cnf"
done

At this point, if the line EXCENTUS_RETAIL_ID is in the file then I want to Print "Yes" and if it is not there, I want to print "No".

Any assistance is greatly appreciated. Thanks.

grail · 09-25-2013, 07:15 AM

I will leave the ssh part to someone with more knowledge, however your for loop is a nightmare.
Read files with while loops:

Code:

while read -r HostName _
do
    <your stuff here>
done</home/techs/hostlist

The underscore simply soaks up the rest of the line and assumes the data is white space separated

ntubski · 09-25-2013, 08:12 AM

One thing to watch out for using a while read with redirected input, is that none of the commands inside the loop should read from it; ssh has the -n option for this:

Code:

while read -r HostName _
do
        echo $HostName
        ssh -n root@$HostName "grep -q EXCENTUS_RETAIL_ID /usr1/vision/vision.cnf && echo yes || echo no"
done</home/techs/hostlist

keif · 09-25-2013, 08:24 AM

Quote:

Originally Posted by grail

I will leave the ssh part to someone with more knowledge, however your for loop is a nightmare.
Read files with while loops:

Code:

while read -r HostName _
do
    <your stuff here>
done</home/techs/hostlist

The underscore simply soaks up the rest of the line and assumes the data is white space separated

Thank you for the advice on using while instead of using cat for the file. I can see why this makes much more sense.

Keith

keif · 09-25-2013, 08:25 AM

Quote:

Originally Posted by ntubski

One thing to watch out for using a while read with redirected input, is that none of the commands inside the loop should read from it; ssh has the -n option for this:

Code:

while read -r HostName _
do
        echo $HostName
        ssh -n root@$HostName "grep -q EXCENTUS_RETAIL_ID /usr1/vision/vision.cnf && echo yes || echo no"
done</home/techs/hostlist

Thank you. This worked perfectly.