Shell script - SSH - linux

I am using shell script to add some file to server. Is there any way to write a shell script that will execute one part on local computer and the other part when you're logged into that server?
For example, I want to log in, do something, add some file, and then I want to list everything on that server.
ssh something#something
I enter password
Then list files from server.

You can just add a command to end of the ssh command; for example:
ssh username#host ls
will run ls on the server, instead of giving you a login shell.

Related

Run bash script after login

I have a bash script with a series of whiptail menus that allows a user to setup their new system, which is Ubuntu server, with no GUI, just CLI (it's going to be a Virtual Machine image).
I'm already forcing a root login by editing /etc/default/grub and /etc/init/tty1.conf, so the user is dropped directly into the root command prompt. From there the user has to type in ./whiptail.sh to start the script and get the whiptail prompts to further setup their host.
Now, I'd like for my script to be what appears up after the the login occurs instead of the user being dropped to the command prompt. How can I do this?
All interactive sessions of bash will read the initialization file ~/.bashrc.
So you can just add the script at the end of the root's .bashrc i.e. /root/.bashrc, assuming the script is executable:
echo '/path/to/whiptail.sh' >>/root/.bashrc
Now the script will be always run when root opens a new interactive shell. If you only want to run while login only, not all all interactive sessions you should rather use ~/.bash_profile/~/.bash_login/~/.profile (the first one available following the order).
If you want it to be global, add you script to
/etc/profile
If you want it to be user-specific, add you script to
/home/$USER/.profile
Consider upvoting the original answer here: https://unix.stackexchange.com/a/56088/343022

How to run shell script in another server in a script?

No where online can i find a way to run a shell script on a remote server from another script. This is for automation, so the script on the host machine will automatically trigger another script on a different server. The server that my script will ssh to will either have a password prompt or have RSA key pair set up
Thanks!
Just pass the command as an argument to ssh.
ssh someserver /path/to/some/script.bsh
Let's say you want to execute a script on node2 but you have your script on node1 file name of script is sp over location /home/user/sp. Simply
ssh node2 < /path-of-the-script-including-the-filename
Another way, using expect package.
Disclaimer: This you can use for testing environments since it has an
open password. but depends on your usecase
If your server does not have expect, you may add the package then. run the command. You can also put this command inside an .sh script.
expect -c 'spawn ssh user#10.11.12.13 "/path/to/my.sh"; expect "assword:"; send "Y0urp#ssw0rd\r"; interact'

call "ssh" in system function in perl

i have a question related to connecting via ssh with "system()" function in perl.
in my perl script i want to connect via ssh to another ip, run a command and return its value or redirect result value to a file.
system ("su - anotherUSer ; ssh someUsername#someIpAddress");
(i change my username so that i am not asked for a password)
when i execute this only line it changes the username correctly but not connects via ssh. In other words, the second part of the system call is not done (or is done but not reflected on the terminal).
If i enter mannualy to the server where this script executes and run this two commands, i can run them without errors.
When i run "exit" command to logout my anotherUser user an error raises:
(ssh: "username"."ip": node name or service name not known)
I also tested it escaping '#' and '.'
system ("su - anotherUSer ; ssh someUsername\#number\.number\.number\.number");
in this case when i run the "exit" command, it askes for the password(Remember that i swiched users so that password could be ommited).
I hope you understand my problem.
Thanks!!!
You're telling the wrong shell to execute ssh.
You spawn a shell and ask it to execute two commands, su and ssh. It first spawns su, which launches another shell. You didn't tell this new shell to do anything, so it waits for input. When it finally exits, the first shell executes the second command, ssh.
Use:
system("su -c 'ssh someUsername#someIpAddress' - anotherUSer");
But that's nasty! Why not just set up a key for the current user instead of becoming anottherUSer to use theirs?

pull a ssh results to variable

if I ssh to another linux env, and run a command that gives me a result, can I grab that ssh result and store it locally? I have a ksh script that run locally on one linux box right now, but I need to get some parameters from another linux box into that script.
Sure, ssh is a command just like any other, but this will be trickier if you want to ssh interactively and do it, but this could work:
var=$(ssh user#host command_with_output)
then $var will show the output of command_with_output
All this works best if ssh doesn't require a password as well

Run bash script upon ssh

I have a host on which I created a script .
The script is being executed whenever the user is logging in via ssh bashrc launches the script.
Now I'm trying to get the script to execute even if the user is not actually logging in , and just running a command .
For example I want the script to be executed if a user is running the following :
ssh user#host.com some_command
Is there a way to achieve the above?
A solution affecting all the users could be using pam-exec and launch a script on the user login event. Check the pam-exec manual page and an example on how to use it pam-exec scripting.
A simple solution for a single user should be add the script in the rc file of the ssh user, add your script to:
~/.ssh/rc
I've done some tests and the rc solution works fine in your case, it gets executed when the user launches a remote command via ssh.
If you don't have a rc file just create it.
you can edit authorized_keys file and add a COMMAND , something like :
command="/home/michale/bin/dothis.sh" ...public key...
for more details read ssh and authorized_keys documentations.

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