Passing file name to get uptimes

Hi:

I am very new to shell scripting, and started writing a script today. I am trying to read a server name from a list that stores server name and passing each server name to get the uptime. What i would to achieve is that, i should get a file with server names along with their uptimes on a separate line.
For example:

Server1 Uptime
server2 Uptime

..and so on

My script:

server_list=`/tmp/hosts.list`

for server in $server_list
do
    while read line
    do
       cut -f1 -d" " //hosts.list has other info like IP address
       upt=`/usr/local/bin/ssh $server uptime`
       printf $server $upt
    done<$server
done

when i run the script i get the following error:

/tmp/hosts.list[1] : server1: not found
/tmp/hosts.list[2] : server2: not found

...and so on

Any help is greatly appreciated!

That's a useless use of backticks and not even correct syntax for that.

I'd try this:

# First column goes in server, all the rest go in OTHERSTUFF
while read SERVER OTHERSTUFF
do
        /usr/local/bin/ssh "$SERVER" printf "${SERVER}: " ';' uptime
done < /tmp/hosts.list

This will print the server's name on the server itself, then run uptime, doing everything in one neat operation with no backticks whatsoever. The quotes around the semicolon are mandatory -- without that, uptime will run locally instead of being considered part of the ssh command...

Thanks Corona...can you also help me here

the updates you made to the script displays only one row and i wanted all 50 servers to be displayed.
My changes are not working either:

server_list='/tmp/hosts.list'

for SERVER in $server_list
do
    while read line
    do
    /usr/local/bin/ssh "$SERVER" printf "${server} : " ';' uptime
    done < $server_list
done

Errors i am getting:

ssh: /tmp/hosts.list: no address associated with name
ssh: /tmp/hosts.list: no address associated with name
ssh: /tmp/hosts.list: no address associated with name
.....

ignore this...

see my other post...(below)

still the similar error:

ssh: no address associated with name
ssh: no address associated with name
ssh: no address associated with name
....

server_list='/tmp/hosts.list'
while read server
do
   uptime=$(ssh $server "uptime")
   echo "$server $uptime" >> output.txt
done < $server_list

this doesnt work either

what error message you are getting ?

---------- Post updated at 08:03 PM ---------- Previous update was at 07:58 PM ----------

make sure, your file should have only the servername

Thanks itkamaraj for the help!

It works partially, i see only the first server with the details in the output file.

The hosts.list file has servers listed in one column like below:

server1
server2
server3
...and so on

Right now, its showing me only the server1 details with the uptime. Can you please help where i can see all 50 servers? Thanks in advance!

SERVERS=$(cat /tmp/hosts.list)
for i in $SERVERS;
do 
uptime=$(ssh $i uptime)
echo "$i $uptime" >> output.txt
done

This looks like an DNS issue. You can add an entry of the servers that you are trying to ssh in the /etc/hosts.

My suggestion was not a skeleton or pseudocode, I expected it to work as-is and you didn't need to modify it to add extra loops. It already had a loop which read servers from your server file one by one and fed them into ssh individually. Did you try my original, unmodified code?

$server_list is a file, therefore, 'for x in $server_list' makes no sense. You read from files.

server_list='/tmp/hosts.list'

while read SERVER
do
    /usr/local/bin/ssh "$SERVER" printf "${SERVER} : " ';' uptime
done < $server_list

Thanks itkamaraj for the help! I made little changes to the script where the contents of the output.txt are being to my email address. So far everything works perfectly.

TODAY=`date "+%Y%m%d"`
export TODAY

SERVERS=$(cat /tmp/hosts.list)
for i in $SERVERS;
do 
uptime=$(ssh $i uptime | cut -f1 -d",")
echo "$i $uptime" >> uptimes_${TODAY}.txt
done

cat uptimes_${TODAY}.txt | mailx -s "Uptimes for `date`" myemail@email.com

I am also trying to think of implementing the following.
If i run the script through crontab on Monday morning, i would like the script to print only the servers who have been up for more than one day, this way only the servers that didnt get rebooted will be mailed to my email address. Any thoughts on how i should be handling? Really appreciate all your help so far.
Cheers!