Review all scripts that run after sshing into a machine - ssh

Is there a way to review everything that runs when I ssh into a machine?
Somehow when I ssh, it starts out with zsh, which is my default shell, but then later changes to fish shell. Want to find out where the fish shell is being called and delete that line.

Yan can add set -vx very early in your various zsh startup scripts ~/.zprofile, ~/.zshrc, etc. If the swicth to fish occurs even earlier, try the same with the zsh startup script in /etc.

Related

How to create a Linux GUI app short cut for WSL2 on Windows10?

I have properly installed and setup WSL2. It works fine.
I also setup X11 forwarding and X server (VcXsrv). I can launch GUI apps such like konsole or gvim or even google-chrome from a bash shell.
Now I want to launch konsole by simply double clicking a short cut on the desktop without launching the bash command mode terminal. How should I do it?
I tried running this in cmd:
> wsl /usr/bin/konsole
and it reports:
qt.qpa.xcb: could not connect to display
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, xcb.
I'm guessing it is because some X11 forwarding configurations were not properly setup, so I created a k.sh as follows:
#!/usr/bin/bash
export DISPLAY=$(cat /etc/resolv.conf | grep nameserver | awk '{print $2; exit;}'):0.0
export LIBGL_ALWAYS_INDIRECT=1
/usr/bin/konsole &
The first two lines were the X11 settings in my .bashrc, the last line launches konsole.
It works fine under bash environment; but when I ran
wsl k.sh
from windows cmd environment, it silently quitted without launching the konsole.
I'm out of ideas. What should I do to directly launch konsole or other Linux GUI apps under windows without having to getting into bash?
Thanks in advance.
You are asking about two different command-lines, and while the failures in running them via the wsl command have the same root-cause, the underlying failures are likely slightly different.
In both cases, the wsl <command> invocation results in a non-login, non-interactive shell where the command simply "runs and exits".
Since the shell is non-login/non-interactive, your startup files (such as ~/.bashrc and ~/.bash_profile, among others) are not being processed.
When you run:
wsl /usr/bin/konsole
... the DISPLAY variable is not set, since, as you said, you normally set it in your ~/.bashrc.
Try using:
wsl -e bash -lic "/usr/bin/konsole"
That will force bash to run as a login (-l), interactive (-i) shell. The DISPLAY should be set correctly, and it should run konsole.
Note that the quotes probably aren't necessary in this case, but are useful for delineating the commands you are passing to bash. More complicated command-lines can be passed in via the quotes.
As for:
wsl k.sh
That's likely a similar problem. You are doing the right thing by setting DISPLAY in your script, but I notice that you aren't using a fully-qualified path it. This would normally work, of course, if your script is in a directory on the $PATH.
But I'm guessing that you might add that directory to the $PATH in your startup config, which means (again) that it isn't being set in this non-login, non-interactive shell.
As before, try:
wsl -e bash -lic "k.sh"`
You could also use a fully-qualified path, of course.
And, I'm fairly sure you are going to run into an issue with trying to put konsole in the background via the script. When WSL exits, and the bash shell process ends, the child konsole process will terminate as well.
You could get around this with a nohup in the script, but then you also need to redirect the stderr. It's probably easiest just to move the & from the script itself to the command-line. Change your k.sh to:
#!/usr/bin/bash
export DISPLAY=$(cat /etc/resolv.conf | grep nameserver | awk '{print $2; exit;}'):0.0
export LIBGL_ALWAYS_INDIRECT=1
/usr/bin/konsole
Then run it with:
wsl -e bash -lic "k.sh &"`
Finally, a side note that when and if you can upgrade to Windows 11, it will automatically create Windows Start Menu entries for any Linux GUI app you install that creates a .desktop file. You can manually create .desktop files to have WSL create Start menu items for most applications.
For reference, in Windows 11 it's easier. To run a GUI application without a terminal window popping up, you just need to call wslg.exe instead of wsl.exe.
So, for example:
target: C:\Windows\System32\wslg.exe konsole
start in: C:\WINDOWS\system32
shortcut key: None
comment: Konsole
This tutorial shows how to install VcXsrv and and edit .bashrc to ensure that the "DISPLAY env var is updated on every restart".
DISPLAY env var needs to be dynamic setting.
I've used it successfully with WSL2 on Windows10 Version 21H2 (OS build 19044.2130) to run Chrome, Edge, and thunar. I'm using the Ubuntu 20.04 Linux distro.
To edit .bashrc follow these instructions.

What is the difference between calling a command via "wsl [command]" and opening a wsl shell and calling "[command]"?

I am using Ubuntu via WSL 2.0 on Windows 10 and would like to run Texlive from the Windows command line. To do so I prepended the Texlive folder to the path in /etc/environment (I also tried a number of other locations eg. $HOME/.bashrc):
C:\Users\scott\Documents>wsl echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/mnt/c/Windows/system32:...
C:\Users\scott\Documents>wsl
scott#SCOTT-PC:/mnt/c/Users/scott/Documents$ echo $PATH
/usr/local/texlive/2020/bin/x86_64-linux:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/mnt/c/Windows/system32:...
Why is there a difference between these two paths? Is it possible to change the first PATH variable?
To be honest, when I first looked at this question, I thought it would be an easy answer. Oh how wrong I was. There are a lot of nuances to how this works.
Let's start with the fairly "easy" part, though. The main difference between the first method and the second:
wsl by itself launches into a login (and interactive) shell
the shell launched with wsl echo $PATH is neither a login shell nor an interactive shell
So the first will source both login scripts (e.g. ~/.profile) and interactive startup scripts (e.g. ~/.bashrc). The second form does not get to source either of these.
You can see this a different way (and get to the solution) with the following commands:
wsl -e bash -c 'echo $PATH'
wsl -e bash -li -c 'echo $PATH'
The -li forces bash to run as a login and interactive shell, thus sourcing all of the applicable startup scripts. And, as #bovquier points out in the comments, a single quote is needed here to prevent PowerShell from interpolating the $ before it gets to Bash. That, or escape it.
You should be able to run TeX Live the same way, just replacing the "echo $PATH" with the startup command you need for TeX Live.
A second option would be to create a script that both adds the path and runs the command, and just launch that script through wsl /path/to/script.sh
That said, I honestly don't think that your current login/interactive PATH is coming from /etc/environment. In my testing, at least, /etc/environment has no use in WSL, and that's to be expected. /etc/environment is only sourced by PAM modules, and with no login check performed by WSL, there's no reason to invoke PAM in either the wsl nor the wsl echo $PATH commands.
I'd expect that you still have the PATH setting in ~/.bashrc or somewhere similar), and that's where the shell is picking it up from at the moment.
While this isn't necessarily critical to understanding the answer, you might also wonder, if /etc/environment isn't used for setting the default (non-login, non-interactive) path in WSL, what is? The answer seems to be that it is hard-coded into the init that starts up WSL. That init is also what appends the Windows path (assuming you don't have that feature disabled in /etc/wsl.conf).

SSH command step not working for one command - in Jmeter

I have a unique problem using jmeter SSH command.
I use this step to run spark jobs.
the problem is that one of the commands not working, to clarify it connects and not get response and just wait and wait for hours, and nothing displayed on screen.
I know how to work with the tool, and this behavior is special for this script alone.
All other script worked, I duplicate one that worked for example
sudo /run_stg.sh this command worked
sudo /run_off2-stg.sh this command not worked
if I run the job manually via jenkins it worked
if I entered to command line and use plik ssh it worked,
the problem is just Jmeter, that is waiting and waiting and I can not understand for what?
the job is about 3 minutes, and I wait for response in Jmeter for 4 hours and nothing Jmeter just waiting.
in the console log I set to trace level and nothing, absolutely no idea how to start handle this issue in Jmeter.
an anyone please assists how to make Jmeter to write what happened?
or just to know if he connect or anything
since this behavior all the test can not be performed
Most probably you are as usual misconfiguring the SSH Command sampler.
The idea is not to run the script per se, you need to delegate the script execution to the Unix Shell, for example Bash this way you will be able to combine several commands together, see the output, amend debugging level, etc.
So I would recommend setting your command to something like /bin/bash -c -x /your/script.sh
Another guess, given you use sudo it might be the case that the sudo command simply waits for the password (which JMeter never provides), if this is the case try amending your script permissions using chmod command and allowing your user its execution without root privileges.
And finally, given you're able to run your command using "plik ssh" (whatever it is) you can run it using OS Process Sampler
More information: How to Run External Commands and Programs Locally and Remotely from JMeter

Reading profile script in non-interactive mode with AIX implementation of ksh

Please note that this is an AIX related question.
I have a jenkins server running on Redhat which is running a node via SSH on an AIX server.
The commands are run non-interactively using SSH to a user on the AIX machine who has ksh as its standard shell.
The problem is that this build needs a number of environment variables, and i can't seem to get it to work.
I have tried:
Jenkins allows me to set some environment variables for the session. So i tried:
ENV="$HOME/.profile"
I tried creating a .kshrc file containing
. .profile
But none of these approaches seems to make KSH run the .profile script.
The .profile script contains the environment setup for the user i need.
How do i get an AIX implementation of KSH to run my .profile script before executing commands?
You need to specifically tell Jenkins that you want to execute them in ksh shell.
By default, Jenkins runs as sh <commands>.
Add a shebang in your shell command as first line,
#!/bin/ksh
Most shells don't source their .profile files on non-interactive sessions. A simple solution is to source the .profile yourself as part of the command you are sending.
So instead of
yourcommand1; yourcommand2
you should send
. ~/.profile; yourcommand1; yourcommand2
over ssh
UPDATE after reading the comment about Jenkins controlling the ssh command
In the case your ssh command is performed by Jenkins you should have a look at https://wiki.jenkins-ci.org/display/JENKINS/SSH+Slaves+plugin, especially the 'Login profile files' paragraph.
I'd say one of these solutions is best
Set all environment variables from Jenkins using the node's configure page. Install the EnvInject plugin to do this.
Write a wrapper around the java command on the slave that sources your profile script and adjust the JavaPath (also on the node's configure page) to point to that wrapper.
The only way I know of for setting environment variables that will apply for non-interactive shells on AIX is via /etc/environment. I believe this is the correct place, but it will of course then apply to all users and all shells.

Default c-shell, change to bash but allow for scp

Hi so I am trying to modify my .cshrc file to make bash my default. It is on a school account so I cannot change the main settings but can change the profile. The problem is that when I use the command:
bash
in my .cshrc it works when I am logging in just fine. But anytime I try to scp files it does not work because it launches the .cshrc and scp gets confused when it changes to the bash terminal.
Does anyone know how to get around this? Possibly launch bash in quiet mode...
In general, you shouldn't do anything that invokes an interactive application or produces visible output in your .cshrc. The problem is that .cshrc is sourced for non-interactive shells. And since your default shell is csh, you're going to have csh invoked non-interactively in a lot of cases -- as you've seen with scp.
Instead, I'd just invoke bash -- or, better, bash -l -- manually from the csh prompt. You can set up an alias like, say, alias b bash -l.
If you're going to invoke a new shell automatically on login (which is still not a good idea), put it in your .login, not your .cshrc.
This is assuming chsh doesn't work, but it should -- try it.