shell script ssh command exit status

Question

In a loop in shell script, I am connecting to various servers and running some commands. For example

#!/bin/bash FILENAME=$1 cat $FILENAME | while read HOST do    0</dev/null ssh $HOST 'echo password| sudo -S     echo $HOST     echo $?          pwd    echo $?' done 

Here I am running "echo $HOST" and "pwd" commands and I am getting exit status via "echo $?".

My question is that I want to be able to store the exit status of the commands I run remotely in some variable and then ( based on if the command was success or not) , write a log to a local file.

Any help and code is appreciated.

Answer 1

ssh will exit with the exit code of the remote command. For example:

$ ssh localhost exit 10 $ echo $? 10 

So after your ssh command exits, you can simply check $?. You need to make sure that you don't mask your return value. For example, your ssh command finishes up with:

echo $? 

This will always return 0. What you probably want is something more like this:

while read HOST; do   echo $HOST   if ssh $HOST 'somecommand' < /dev/null; then     echo SUCCESS   else     echo FAIL done 

You could also write it like this:

while read HOST; do   echo $HOST   if ssh $HOST 'somecommand' < /dev/null   if [ $? -eq 0 ]; then     echo SUCCESS   else     echo FAIL done 

Answer 2

You can assign the exit status to a variable as simple as doing:

variable=$? 

Right after the command you are trying to inspect. Do not echo $? before or the new value of $? will be the exit code of echo (usually 0).