Bash script does not ssh all the entries of a csv file - linux

I am trying to patch a bunch of CENT OS machines with the latest fix pack. I have the below bash script that takes csv file as a input which has the ip address and password for those machines.
The code works fine however, it would only work for the first row it does not seem to be working for the rest of the list as my output.txt only has the entry only for the first row host .
patch.sh
INPUT=hosts_test.cvs
OLDIFS=$IFS
IFS=,
[ ! -f $INPUT ] && { echo "$INPUT file not found"; exit 99; }
while read privateip password
do
sshpass -p$password ssh -t -o "StrictHostKeyChecking no" user123#$privateip "
hostname
hostname -I --all-ip-addresses
sudo yum -y update bash
env x='() { :;}; echo vulnerable' bash -c \"echo If you see the word vulnerable above, then you are vulnerable to shellshock\"
echo ""
exit
" >> output.txt
done < $INPUT
IFS=$OLDIFS
hosts_test.cvs
10.xxx.xx.219,abcd~qY1
10.xxx.xx.226,l4~abcdefg
10.xxx.xx.221,l4#abcdefgh
Terminal Output
Pseudo-terminal will not be allocated because stdin is not a terminal.

Add at the end of your sshpass command </dev/null.

Add Defaults:username !requiretty to your /etc/sudoers config
Get rid of -t from your ssh command
Optional, but recommended: set up public key auth so you don't have your passwords lying around in text files.

You can pass ssh another -t to force pty allocation:
ssh -t -t

Related

Error when stacking SSH command arguments within a bash script using other scripts as variables

I have a csv file called addresses.csv which looks like this,
node-1,xx.xxx.xx.xx,us-central-a
....
node-9,xxx.xx.xxx.xx,us-east1-a
I have a script below called 0run.sh,
#!/bin/bash
username='user'
persist="bash /home/${username}/Documents/scripts/disk/persistentDisk.sh"
first="bash /home/${username}/Documents/scripts/disk/firstAttach.sh"
while IFS=, read -r int ip <&3; do
if [ "$int" == "node-1" ]; then
--->ssh -i ~/.ssh/key -o StrictHostKeyChecking=no -l ${username} ${ip} "${persist}; ${first}"<---
else
ssh -i ~/.ssh/key -o StrictHostKeyChecking=no -l ${username} ${ip} "${first}"
fi
done 3<addresses.csv
The error occurs in the part of the code where I drew the arrows.
When it runs on node-1, instead of running ..persistentDisk.sh followed by ..firstAttach.sh, it only runs ..persistentDisk.sh and gives me the following error before it runs ..persistentDisk.
bash: /home/user/Documents/scripts/disk/firstAttach.sh: No such file or directory
The rest of the script runs completely fine. The only error occurs at this one part where it misses the 2nd script.
When I run the command like this it runs fine.
ssh -i ~/.ssh/key -o StrictHostKeyChecking=no -l ${username} ${ext} "${first}"
When I run it like this, it runs fine as well.
ssh -i ~/.ssh/key -o StrictHostKeyChecking=no -l user xxx.xx.xxx.xx "bash /home/${username}/Documents/scripts/disk/persistentDisk.sh; bash /home/${username}/Documents/scripts/disk/firstAttach.sh"
When I run the command like with a \ before the ; to escape it like this,
ssh -i ~/.ssh/key -o StrictHostKeyChecking=no -l ${username} ${ext} "${persist}\; ${first}"
I get the following error, and neither scripts run within the node-1 part of the code, but the rest of the code's else loops run fine.
bash: /home/user/Documents/scripts/disk/persistentDisk.sh;: No such file or directory
Why can't I stack the 2 commands within the if statement in the ssh using variables?
If I clearly understand: your real problem consist to leave STDIN free for interaction in target host!
About read and redirection
Try using:
#!/bin/bash
username='user'
persist="bash /home/${username}/Documents/scripts/disk/persistentDisk.sh"
first="bash /home/${username}/Documents/scripts/disk/firstAttach.sh"
while IFS=, read -r -u $list int ip foo; do
if [ "$int" == "node-1" ]; then
echo CMD... $ip, $persist
else
[ "$ip" ] && echo CMD... $ip, $first
fi
done {list}<addresses.csv
Tested, this èroduce:
CMD... xx.xxx.xx.xx, bash /home/user/Documents/scripts/disk/persistentDisk.sh
CMD... xxx.xx.xxx.xx, bash /home/user/Documents/scripts/disk/firstAttach.sh
-u flag to read, tell to use file descriptor ${list} instead of STDIN
foo is some useless variable used to prevent rest of line to be stored in $ip (xx.xxx.xx.xx,us-central-a in this case)
{list}</path/to/filename create a new variable by finding any free file descriptor.
About ssh (and redirection)
You could use:
#!/bin/bash
username='user'
persist="/home/${username}/Documents/scripts/disk/persistentDisk.sh"
first="/home/${username}/Documents/scripts/disk/firstAttach.sh"
while IFS=, read -r -u $list int ip foo; do
[ "$int" = "node-1" ] && cmd=persist || cmd=first
[ "$ip" ] && ssh -i ~/.ssh/key -t -o StrictHostKeyChecking=no \
-l ${username} ${ext} /bin/bash "${!cmd}"
done {list}<addresses.csv
By using this syntax, you will keep STDIN free for script running on target host.

how to use value that is calculated inside ssh

I have linux script like below:
sshpass -p "pwd" ssh -tt user << 'EOF'
cd /directory
file=$(ls -1t | head -1)
exit
EOF
How to use the file parameter outside ssh. That is after EOF statement.
I think that you have to work with the output of the SSH command to capture it into a local variable.
This could be a viable solution (tried with obviously different parameters locally, OS Ubuntu 17.04):
CMD=`cat <<EOF
cd /directory
ls -1t | head -1
EOF`
FILE=`sshpass -p "pass" ssh -t user#host -o LogLevel=QUIET "$CMD"`
echo "$FILE"

Commands don't echo after sudo as another user

I have a single command to ssh to a remote linux host and execute a shell script.
ssh -t -t $USER#somehost 'bash -s' < ./deploy.sh
Inside deploy.sh I have this:
#!/bin/bash
whoami; # I see this command echo
sudo -i -u someoneelse #I see this command echo
whoami; # I DON'T see this command echo, but response is correct
#subsequent commands don't echo
When I run the deploy.sh script locally all commands echo.
How do I get commands to echo after I sudo as another user over ssh?
Had to set -x AFTER sudo as another user
#!/bin/bash
whoami;
sudo -i -u someonelese
set -x #make sure echo on
whoami; #command echoed

pseudo-terminal error will not be allocated because stdin is not a terminal - sudo

There are other threads with this same topic but my issue is unique. I am running a bash script that has a function that sshes to a remote server and runs a sudo command on the remote server. I'm using the ssh -t option to avoid the requiretty issue. The offending line of code works fine as long as it's NOT being called from within the while loop. The while loop basically reads from a csv file on the local server and calls the checkAuthType function:
while read inputline
do
ARRAY=(`echo $inputline | tr ',' ' '`)
HOSTNAME=${ARRAY[0]}
OS_TYPE=${ARRAY[1]}
checkAuthType $HOSTNAME $OS_TYPE
<more irrelevant code>
done < configfile.csv
This is the function that sits at the top of the script (outside of any while loops):
function checkAuthType()
{
if [ $2 == linux ]; then
LINE=`ssh -t $1 'sudo grep "PasswordAuthentication" /etc/ssh/sshd_config | grep -v "yes\|Yes\|#"'`
fi
if [ $2 == unix ]; then
LINE=`ssh -n $1 'grep "PasswordAuthentication" /usr/local/etc/sshd_config | grep -v "yes\|Yes\|#"'`
fi
<more irrelevant code>
}
So, the offending line is the line that has the sudo command within the function. I can change the command to something simple like "sudo ls -l" and I will still get the "stdin is not a terminal" error. I've also tried "ssh -t -t" but to no avail. But if I call the checkAuthType function from outside of the while loop, it works fine. What is it about the while loop that changes the terminal and how do I fix it? Thank you one thousand times in advance.
Another option to try to get around the problem would be to redirect the file to a different file descriptor and force read to read from it instead.
while read inputline <&3
do
ARRAY=(`echo $inputline | tr ',' ' '`)
HOSTNAME=${ARRAY[0]}
OS_TYPE=${ARRAY[1]}
checkAuthType $HOSTNAME $OS_TYPE
<more irrelevant code>
done 3< configfile.csv
I am guessing you are testing with linux. You should try add the -n flag to your (linux) ssh command to avoid having ssh read from stdin - as it normally reads from stdin the while loop is feeding it your csv.
UPDATE
You should (usually) use the -n flag when scripting with SSH, and the flag is typically needed for 'expected behavior' when using a while read-loop. It does not seem to be the main issue here, though.
There are probably other solutions to this, but you could try adding another -t flag to force pseudo-tty allocation when stdin is not a terminal:
ssh -n -t -t
BroSlow's approach with a different file descriptor seems to work! Since the read command reads from fd 3 and not stdin,
ssh and hence sudo still have or get a tty/pty as stdin.
# simple test case
while read line <&3; do
sudo -k
echo "$line"
ssh -t localhost 'sudo ls -ld /'
done 3<&- 3< <(echo 1; sleep 3; echo 2; sleep 3)

getting user input while SSH'ed into another box

I have a bash script that basically should work like below:
get build number from user and put it in buildNum var
prep the build on local machine by calling a local script with buildNum as it's argument
sftp the prepped zip file to remote server1
Do this:
ssh -v $server1 <<EOF
rm -rvf path1-on-remote-server1/*
cd path2-on-remote-server1
unzip ../prepped-zip-file-$buildNum.zip
exit
EOF
sftp the prepped zip file to remote server2
The problem i am having is that on the forth step of number 4, $buildNum is not known to the remote server and it fails.
I tried the following two solutions and both failed:
use double quotes "unzip ../prepped-zip-file-$buildNum.zip" which resulted in "unzip ../prepped-zip-file-11.6.zip: Command not found.
tried to get the build number again from the user during the SSH session which failed again by not even waiting for my input and looking for a zip file without the build number at the end of the name, as the var was empty,
i did :
ssh -v $server1 <<EOF
rm -rvf path1-on-remote-server1/*
cd path2-on-remote-server1
echo "enter build num once more: "
read bNum
unzip ../prepped-zip-file-$bNum.zip
exit
EOF
Any suggestions on how to achieve what i am after.
Thanks in advance
Are you sure this doesn't work?
ssh -v $server1 <<EOF
rm -rvf path1-on-remote-server1/*
cd path2-on-remote-server1
unzip ../prepped-zip-file-$buildNum.zip
exit
EOF
When I try it on my machine, with cat instead of ssh -v $server1 for testing, the variable does get substituted into the here-document, just as if the entire document had been on a command line. The remove shell never needs to know there was a variable in the first place.
Actually, though, you may want to give the remote command on the ssh command line rather than redirecting the standard input. This would be more robust in case some of the parts of it unexpectedly decide to try reading from stdin:
ssh -v $server1 "rm -rvf path1-on-remote-server1/*
cd path2-on-remote-server1
unzip ../prepped-zip-file-$buildNum.zip"
(Note that multi-line double-quoted strings are okay with bash).
#!/bin/sh
printf "Enter Build Number: "
read BUILD_NUM
cat << EOF | ssh $server1
hostname
echo "${BUILD_NUM}"
uptime
EOF
That works for me.

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