how can I pass $line to the cmd command?
#!/bin/bash
while read line
do
sshpass -p "..." ssh -o StrictHostKeyChecking=no -tt windows#172....-p 333 cmd /c "cd C:\ & download_give_id.exe '$#$line' "
done <apps.txt
Basically, if you want to interpolate a variable into a bash string you need to use double quotes instead of single quotes:
str="${var} foo bar" # works
str='${var} for bar' # works not
In the special case that you are running ssh commands inside a while loop, I strongly recommend to pass /dev/tty explicitly as input to the command since once the remote command should read from stdin - for whatever reason - it will slurp stdin of the while loop otherwise:
while read line ; do
ssh ... -- "${line} ..." < /dev/tty # Pass tty to stdin
done < input.txt
Note: The above command will work only if the process has been started in a terminal. If the process is not running in a terminal, you need to pass something else as stdin for the inner ssh command.
Related
I am using the shell module to execute the following command
tasks:
- name: Command
shell: "sshpass -p 123 ssh -o 'StrictHostKeyChecking no' root#10.67.13.50 shell << EOF \n whoami\nEOF | cat"
I am getting the following error
"stderr_lines": [
"/bin/sh: line 2: warning: here-document at line 0 delimited by end-of-file (wanted `EOF')",
"Warning: Permanently added '10.67.13.50' (ECDSA) to the list of known hosts.",
"bash: shell: command not found"
]
What is wrong with my command?
tl;dr you can either a) replace shell with sh or bash, or b) replace shell with whoami and drop the heredoc.
Let's decompose the shell command:
sshpass -p 123 ssh -o 'StrictHostKeyChecking no' root#10.67.13.50 shell << EOF \n whoami\nEOF | cat
There are several processes happening here.
A sh pipeline with two subprocesses:
sshpass which then runs as a subprocess…
ssh which connects to 10.67.13.50 and runs…
shell with \n whoami\n as its standard input
… and cat, which takes the output from the sshpass process hierarchy
There are a couple potential bugs:
You can safely remove cat from the pipeline.
As #KamilCuk mentioned, cat reads from its input and writes it out. It isn't doing anything here; it's neither useful nor harmless.
shell is not a command on the remote server (10.67.13.50). If you want to run a shell, typically sh or bash is used.
Moreover, you can replace the entire shell … EOF sequence with whoami.
The << EOF \n whoami \nEOF is a heredoc to tell the shell on the remote server what commands to execute. However, there is only one command executed.
In summary, the shell: line could be rewritten as:
sshpass -p 123 ssh -o 'StrictHostKeyChecking no' root#10.67.13.50 whoami
… an odd command, since we know the remote user root.
I have a script something like below
sshpass -p "pwd" ssh -tt user#host << EOF
cd /directory
file=$(ls -1t| head -1)
exit
EOF
cd /directory is changing the directory successfully inside shell. But ls gives the result which is outside the shell. The result of ls is same as when executed outside ssh. Please help in this.
The $(...) part is being evaluated by the outer shell. You can disable this by quoting 'EOF' so that $(...) is passed to the remote shell. It's akin to using single quotes instead of double quotes with regular strings.
sshpass -p "pwd" ssh -tt user#host << 'EOF'
cd /directory
file=$(ls -1t| head -1)
exit
EOF
Below is an example of a ssh script using a heredoc (the actual script is more complex). Is it possible to use both local and remote variables within an SSH heredoc or command?
FILE_NAME is set on the local server to be used on the remote server. REMOTE_PID is set when running on the remote server to be used on local server. FILE_NAME is recognised in script. REMOTE_PID is not set.
If EOF is changed to 'EOF', then REMOTE_PID is set and `FILE_NAME is not. I don't understand why this is?
Is there a way in which both REMOTE_PID and FILE_NAME can be recognised?
Version 2 of bash being used. The default remote login is cshell, local script is to be bash.
FILE_NAME=/example/pdi.dat
ssh user#host bash << EOF
# run script with output...
REMOTE_PID=$(cat $FILE_NAME)
echo $REMOTE_PID
EOF
echo $REMOTE_PID
You need to escape the $ sign if you don't want the variable to be expanded:
$ x=abc
$ bash <<EOF
> x=def
> echo $x # This expands x before sending it to bash. Bash will see only "echo abc"
> echo \$x # This lets bash perform the expansion. Bash will see "echo $x"
> EOF
abc
def
So in your case:
ssh user#host bash << EOF
# run script with output...
REMOTE_PID=$(cat $FILE_NAME)
echo \$REMOTE_PID
EOF
Or alternatively you can just use a herestring with single quotes:
$ x=abc
$ bash <<< '
> x=def
> echo $x # This will not expand, because we are inside single quotes
> '
def
remote_user_name=user
instance_ip=127.0.0.1
external=$(ls /home/)
ssh -T -i ${private_key} -l ${remote_user_name} ${instance_ip} << END
internal=\$(ls /home/)
echo "\${internal}"
echo "${external}"
END
I would like to connect to different shells (csh, ksh etc.,) and execute command inside each switched shell.
Following is the sample program which reflects my intention:
#!/bin/bash
echo $SHELL
csh
echo $SHELL
exit
ksh
echo $SHELL
exit
Since, i am not well versed with Shell scripting need a pointer on how to achieve this. Any help would be much appreciated.
If you want to execute only one single command, you can use the -c option
csh -c 'echo $SHELL'
ksh -c 'echo $SHELL'
If you want to execute several commands, or even a whole script in a child-shell, you can use the here-document feature of bash and use the -s (read commands from stdin) on the child shells:
#!/bin/bash
echo "this is bash"
csh -s <<- EOF
echo "here go the commands for csh"
echo "and another one..."
EOF
echo "this is bash again"
ksh -s <<- EOF
echo "and now, we're in ksh"
EOF
Note that you can't easily check the shell you are in by echo $SHELL, because the parent shell expands this variable to the text /././bash. If you want to be sure that the child shell works, you should check if a shell-specific syntax is working or not.
It is possible to use the command line options provided by each shell to run a snippet of code.
For example, for bash use the -c option:
bash -c $code
bash -c 'echo hello'
zsh and fish also use the -c option.
Other shells will state the options they use in their man pages.
You need to use the -c command line option if you want to pass commands on bash startup:
#!/bin/bash
# We are in bash already ...
echo $SHELL
csh -c 'echo $SHELL'
ksh -c 'echo $SHELL'
You can pass arbitrary complex scripts to a shell, using the -c option, as in
sh -c 'echo This is the Bourne shell.'
You will save you a lot of headaches related to quotes and variable expansion if you wrap the call in a function reading the script on stdin as:
execute_with_ksh()
{
local script
script=$(cat)
ksh -c "${script}"
}
prepare_complicated_script()
{
# Write shell script on stdout,
# for instance by cat-ting a here-document.
cat <<'EOF'
echo ${SHELL}
EOF
}
prepare_complicated_script | execute_with_ksh
The advantage of this method is that it easy to insert a tee in the pipe or to break the pipe to control the script being passed to the shell.
If you want to execute the script on a remote host through ssh you should consider encode your script in base 64 to transmit it safely to the remote shell.
I have bash script (for example):
ssh -t -t user#domain.com << EOF
cd /home/admin
mkdir test
echo 'Some text'
exit
EOF
Can I display only "echo" command in terminal? It is possible?
Now all commands are displayed.
Thank you
Specifying the commands on standard input with ssh -t causes the commands to be echoed back, but you don't have to do that.
ssh -t user#domain.com "
cd /home/admin
mkdir test
echo 'Some text'"
(The exit isn't really required or useful, so I left it out.)
Use single quotes if you want to prevent the local shell from interpolating variables etc in the string containing the commands.
To selectively display an individual command as well as its output, you can use something like
sh -vc 'echo \"Some text\"'
although the nested quoting can start getting on your nerves pretty quickly.