So I've got dozens of servers I connect to and want a simple Ruby script that provides me with a list of those servers. Picking one will start up SSH with the proper connection details and let me start using it. That's it!
But, I don't want/need Ruby to keep running. If I did I could use Net::SSH and capture all output and send it back to the user, but this is an extra layer I don't need. I simply want to use Ruby as a "script starter" and then close itself.
Any ideas? I've thought about forking processes but I don't know how I'd attach the terminal to the new ssh one.
I have a simple bash script that does this already, but I want to add more functionality like being able to add to the list, remove servers, etc. all from the command line. I'm sure I could do this with bash as well but I'm much more comfortable with Ruby.
Maybe exec will do the trick
http://en.wikipedia.org/wiki/Exec_(operating_system)
http://ruby-doc.org/core/classes/Kernel.html#M005968
Related
Im writing a tool and one of its commands allows you to start a new session
How can I make a golang program restart itself? If your solution is OS-Strict im on Linux.
I tried
// exec from os/exec
exec.Command(os.Args[0]).Run()
but it doesnt work. I get a blank input session which is hard to explain
My Program Input: session new
:(
:(
each of the :( represent a blank line where im able to type stuff and hit enter, there are 2 which means i hit enter twice
Im expecting
My Program Input: session new
My Program Input:
Edit: more accurately, i want to make a subprocess of the same program
You could use a separate process, like radovskyb/gobeat.
Example:
sudo gobeat -pid=1234 -cmd="go run sendemail.go"
Run with sudo so gobeat will restart the server in the same terminal tty that it originated in. (sudo)
Point gobeat to the process of the running server that you want gobeat to monitor. (gobeat -pid=1234)
Set the cmd flag to run a Go file that will send an email notifying you that the server was restarted. (-cmd="go run sendemail.go")
If you do not want a separate process, then consider implementing a graceful upgrade
You can use the library cloudflare/tableflip for instance.
Until we can implement our new HEAT SM system i am needing to create some workflows to ease our currently manual user administration processes.
I intend to use Powershell to execute the actual tasks but need to use VBS to send an argument to PS from an app.
My main question on this project is, Can an argument be sent to an already running Powershell process?
Example:
We have a PS menu app that we will launch in the AM and leave running all day.
I would love for there to be a way to allow PS to listen for commands/args and take action on them as they come in.
The reason I am wanting to do it this way is because one of the tasks needs to disable exchange features and the script will need to establish a connection a remote PSsession which, in our environment, can take between 10-45 seconds. If i were to invoke the command directly from HEAT (call-logging software) it would lock up while also preventing the tech from moving on to another case until the script terminates.
I have searched all over for similar functionality but i fear that this is not possible with PS.
Any suggestions?
I had already setup a script to follow this recommendation but i was curious to see if there was a more seamless approach
As suggested by one of the comments by #Tony Hinkle
I would have the PS script watch for a file, and then have the VBScript script create a file with the arguments. You would either need to start it on another thread (since the menu is waiting for user input), or just use a separate script that in turn starts another instance of the existing PS script with a param used to specify the needed action
I'm used to Python Fabric in the past and I'm trying to do something similar with Ruby.
Basically I have created a Rake script which will run as a particular user which has SSH keys setup for passwordless access to the boxes in question.
I've managed to use https://github.com/seattlerb/rake-remote_task in order to run a command remotely, and expected the "put" method to "just work". However it seems to be an Rsync wrapper which does not take advantage of the keyless authentication.
It also seems to expect the file to be generated by a template which is not what I want, I want to SCP an actual .tgz binary file.
Am I missing something in the Ruby/Rake ecosystem. I expected this to be easy, but I feel like I'm going to need to go back to searching for gems?
I'd like to write a shell script that does something like the following
while read line; do
echo $line
done<input.txt | ssh > output.txt
This is a bit pseudo codey at the moment (the original is at work), but you should be able to tell what it's doing. For simple applications this works a treat, but ssh checks the input to see whether it's stdin is a terminal.
Is there a way to fool ssh into thinking that the contents of my piped loop are a terminal rather than a pipe?
EDIT : Sorry for not adding this originally, this is intended to allow ssh to log in via the shell script (answering the password prompt)
ssh -t -t will do what you want - this tells ssh to allocate a pseudo terminal no matter whether it is actually running in one.
Update
This problem (after updating your question and various comments, it became clear you are looking for a way to conveniently get public key encryption into place) could perhaps be solved by 'thinking upside down'.
Instead of trying very hard to get your clients public key onto a server that doesn't yet authenticate the client, you can try to receive an authenticated identity (private key) from that server.
Simple terms: generate a keypair on the server instead of the client, and then find a way to get the keypair on the client. The server can put the public key in it's authorized_keys in advance, so the client can connect right away.
Chances are that
the problem of getting the key across is more easily solved (you could even use a 'group' key for access from various clients)
if a less-secure mechanism is chosen (convenience over security) at least only the security of the client is reduced, not as-much that of the server (directly).
Original answer:
Short answer: Nope. (it would be a security hole for ssh, because ssh 'trusts' the tty for password entry, and the tty only)
Long answer, you could try to subvert/creatively use a terminal emulator (look at script/scriptreplay for inspiration).
Why would you want to do it?
Is there way to invoke a CakePHP console shell on server without shell access? I have written a shell for performing some once off (and hence not a cron task) post DB upgrade tasks.
I could always just copy the logic into a temporary controller, call its actions via http and then delete it, but was wondering if there was a better way to go about it.
It seems that this is a one off script you might want to typically be running after DB updates right?
If that's the case, you can make it part of your "DB update script"
If you use anything like capistrano, you can include there too.
In all cases, if you don't want to touch the shell, I agree that having a controller to call the console code (or any php file running exec() as mentioned previously) would do the trick.
Also, if you want to run it just once and have it scheduled - don't forget that you have the "at" command (instead of cron) which will run it at that scheduled date (see http://linux.about.com/library/cmd/blcmdl1_at.htm)
Hope it helps,
Cheers,
p.s: if its a console shell and you don't want to run it from the console, then just don't make it a console shell.
I have to agree with elvy. Since this is something that you need to do once in a while after other events have happened, why not just create an 'admin' area for your application and stick code for that update in there?
you may be able to use php's exec function to call it from any old php script.
http://www.php.net/exec