I am trying to do something like this:
I have a ssh session connected via paramiko. Now I want to issue commands that depends on the previous commands.
For eg; I first issue a 'cd ~/my_folder' and then a 'ls', since the ssh sessions are seperate for each of the command, my first command will not affect the second command.
How do I maintain sessions across multiple commands? I use the ssh.exec_command() function to issue the commands.
I know I can do something like, ssh.exec_command('cd ~/my_folder; ls') but, let's just assume that I cannot do that in my environment.
You can use SSHClient.invoke_shell to start an interactive shell. You can set the prompt to some easily recognized value then send commands and scan through received data looking for the prompt to demarcate the returned data.
Another option is to use pexpect's pxssh module which has done some of the heavy lifting for you.
Related
I'd like to run a remote bash shell that is fully interactive.
The client side should be able to send commands to this bash process and get the outputs interactively.
This means that, just like in a local bash prompt, the correlation between commands and their respected responses isn't necessarily guaranteed, since we may get outputs from a previous command that runs in the background, after running another command.
It works when I run separate bash process and use pipes:
bash 2>&1 | tee file
bash > file 2>&1
However, if I need to send control characters like Tab for auto-completion or Ctrl+C, in case we want to terminate the current command.
It may sound similar to SSH protocol, but I'd like to experiment with this option of running an alternative remote shell, with different access control and UI experience.
So, my question is: How do I pass the control character to the remote bash process (for example, the auto-completion) and get back the results (for example, list of choices for auto-completion)?
NOTE: I don't wish to develop bash equivalent shell script, but just build a proxy process that is able to pass both data and control characters and provide seamless bash experience as in local /ssh mode.
When I log onto my assorted PCs I usually have a number of things I want to happen automatically, but not always straight away.
These include starting terminal sessions in specific locations on specific desktops (because you get used to using the same layout) and those terminal sessions performing specific acts such as ssh commands. However sometimes when you logon after a reboot you may not want to execute those commands immediately as a higher priority action may need your attention first.
So....what I want is my login script to open terminal sessions and have the session commands pre populated on the command line, but not yet executed.
I use Mate and Compiz as my DE as I like its flexibility.
So in my login script I currently have commands such as.....
mate-terminal --window-with-profile=default --geometry=85x24+180+400 --title='SSH1' &
mate-terminal --window-with-profile=default --geometry=85x24+180+1080 --title='VNC1' &
mate-terminal --window-with-profile=default --geometry=85x24+1305+400 --title='SSH2' &
mate-terminal --window-with-profile=default --geometry=85x24+1305+1080 --title='VNC2' &
These are dedicated mate-terminal sessions that I then enter a ssh and vnc command respectively to connect to some remote boxes. They always open in the same workspace and as can be seen open at a specific location so I always know exactly where I expect them to be.
However I don't want to use the option to say have the ssh command built into the script (as ssh is time sensitive to the receiver and I may not get to it straight away), instead I want to have the command already pre populated in the terminal session so when I do get to it I don't have to type in the whole command each time.
I had looked at using expect to do this and have that working thus
#!/usr/bin/expect -f
# Get a bash shell
spawn -noecho bash
# wait for a prompt
expect ">:"
# type something
send "ssh root#192.168.1.1"
# Hand over control
interact
exit
however I can't see a way of using expect that allows me to spawn the mate-terminal session at specific geometry locations (possibly I'm missing something obvious as I haven't used expect before).
I also don't want to autologon to the ssh sessions using something like a bash 'mate-terminal -c' option as at times the machine may not be network connected which means I'll have a load of potentially messed up attempted connects.
So in recap.
Bash login script.
Opens mate-terminal session at specific geometry locations with command line pre populated with desired command but not yet executed.
Ideas?
I need to run a shell script that should interact with couple of servers / routers in daily schedule. The script will simply login to the remote end, run a command. Up to here i hear that you are saying it is easy. The real problem here is that i need to analyze the output of the first command and based on the output i need to organize the second command. This is also doable, but the situation here is that i do not want to login and logout from the box for every command.
What i need is to login once, stay alive ,run the command take the output, analyze it and then run the second command later on logout and close connection.
Correct me if i am wrong but expect is not an option here. I want to ask for your suggestions.
Which language / module of this language i can use to complete this requirement.
Environment is not pure ssh, so i should have something general that can be used for both ssh/telnet.
Thanks in advance
Since you mentioned python, pexpect should do the job pretty well:
https://pexpect.readthedocs.org/en/latest/overview.html
I have to connect to a linux server from my own Ubuntu machine and operate directly on the server.
A dozen of folder names are listed in a LIST file. How to write sth. (like a bash script?) to carry out the following procedures?
for fold_name in LIST {
/******on my own Ubuntu*******/
-- open 2 new tabs of prompt terminal
-- run an ssh command in both
-- then input passwd and log in automatically in both
/******on the linux server*******/
-- cd to directory xxx/fold_name in both
-- run aaa.exe in 1st tab
-- vim sth in the 2nd tab
}
Once the loop of open-tab-login is solved, I guess the second part is routine as simple bash script except that I don't know how to specify between 2 tabs, either.
The point is I want all tabs in the same terminal. To this end, manually, I often Ctrl+Alt+T to create a prompt and Ctrl+Shift+T to open many tabs within it. And ssh...cd...... in each one. You see how annoying and cumbersome it is!
There are a few things you might like to research, which will get you a little closer.
You can run an ssh without a password, if you use an ssh key. Check out ssh-keygen, and the -i option in ssh.
Opening up tabs in gnome-terminal can be done via the method described here: Open a new tab in gnome-terminal using command line
You can run specific commands (e.g. aaa.exe) on a remote box over ssh, by including the command after the ssh: ssh user#remotehost aaa.exe.
If you want multiple commands, try enclosing them in quotes: ssh user#remotehost "cd /xxx; aaa.exe". Vim does not need to be in the directory in question in most cases: ssh user#remotehost vim /xxx/filename"
If you want to do something interactive (like vim), include the -t flag in ssh.
The tabs will be independent of each other - I'd probably run half of the command in one window, the other (e.g. runnning aaa.exe in one window, using one command, and the vim in another window, using another command, that I just happen to run at the same time. This way I can resize the windows, and arrange them relative to each other, and see both at once.
-- open 2 new tabs of prompt terminal
This depends on which desktop you're using. For gnome, gnome-terminal takes the -e option to specify the script to execute in the new terminal window. So, for something like this, you would execute gnome-terminal -e $script &, placing each instance of gnome-terminal in the background.
If you're using a different desktop, other terminal applications typically have a similar option. So, you'd point the terminal application to a script that's going to run in the terminal, and complete the rest of your task for you.
-- run an ssh command in both
-- then input passwd and log in automatically in both
This is going to be more complicated. The classical solution is the expect utility. There might be other similar tools that do similar things, but expect is pretty much the usual way these kinds of things have been done in the past. When it comes to trying to automate an interactive application, expect is really the only way to go. Unfortunately, expect uses a somewhat arkane syntax, that first-time users typically find confusing, and hard to understand. I grumble, every time I see no other alternative but to use expect to automate something, but this is pretty much the only option that's usually available.
We have put together a perl script that essentially looks at the argument that is being passed to it checks if is creating or modifying a file then it saves that in a mysql database so that it is easily accessible later. Here is the interesting part, how do I make this perl script run before all of the commands typed in the terminal. I need to make this dummy proof so people don't forget to run it.
Sorry I didn't formulate this question properly. What I want to do is prepend to each command such that each command will run like so "./run.pl ls" for example. That way I can track file changes if the command is mv or it creates an out file for example. The script pretty much takes care of that but I just don't know how to run it seamlessly to the user.
I am running ubuntu server with the bash terminal.
Thanks
If I understood correctly you need to execute a function before running every command, something similar to preexec and precmd in zsh.
Unfortunately bash doesn't have a native support for this but you can do it using DEBUG trap.
Here is a sample code applying this method.
This page also provide some useful information.
You can modify the ~/.bashrc file and launch your script there. Do note that each user would (and should) still have the privelege to modify this file, potentially removing the script invocation.
The /etc/bash.bashrc file is system-wide and only changeable by root.
These .bashrcs are executed when a new instance of bash is created (e.g. new terminal).
It is not the same as sh, the system shell, that is dash on Ubuntu systems.