how to keep program running after closing ssh session

fakie_flip · 08-08-2006, 01:15 AM

I am logged into a computer through ssh. I would like to run a program and have it keep running after I log out. How can I do that?

b0uncer · 08-08-2006, 01:25 AM

One means of doing this is probably a program called screen. There are surely other ways but this is quite an easy one; screen can be thought as a virtual terminal, so what you get visually is that you can start a program using screen, then (put it in the background if you like and) "detach" it after which it keeps running even if you log out/close your ssh connection. When you come back, you can "reattach" it again and have control over the program - it won't die when you close the connection.

Read more from google, search LQ etc...and make sure you've got screen installed

http://jmcpherson.org/screen.html has some quick info on how to use this..

jschiwal · 08-08-2006, 01:45 AM

If you don't need to re-attach later, you could also use "nohup".

reddazz · 08-08-2006, 02:27 AM

fakie_flip I've edited the thread title to better reflect your problem.

dalek · 08-08-2006, 06:17 AM

I have used screen for just this reason. It works very well. It took me a bit to understand the key sequence to detach though. Press and hold ctrl and hit the a key, Then press the d key to detach. The ctrl a tells it the next key is a command and the d is for detach. That should help you a little bit.

JZL240I-U · 08-09-2006, 07:11 AM

Possibly stupid question as I don't use ssh: Why not simply use a <command &> and all should be well?

dalek · 08-09-2006, 08:11 AM

I have never tried this but I think if he logs out it will kill the command. I THINK being the key words there.

JZL240I-U · 08-09-2006, 08:15 AM

Umm, doesn't the &-operator detach the process from the console? When you use it and list the processes with "ps ax" or "top" they have their own PID and potter about in the background. But I'm no expert either

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rahulk · 08-09-2006, 08:21 AM

Quote:

Originally Posted by JZL240I-U

Umm, doesn't the &-operator detach the process from the console? When you use it and list the processes with "ps ax" or "top" they have their own PID and potter about in the background. But I'm no expert either

.

The & puts the command in the backgroud. The command nohup detaches the process from the terminal. If the job is put as a background process then on exiting the console, the parent PID will change to 1 but the terminal will remain. Hence a process can be kept running either by putting it as a background job or by nohup command.

vsluzky · 10-09-2011, 01:37 PM

Start your <command-with-parameters> as:
nohup <command-with-parameters> &

u4david · 11-03-2011, 09:33 AM

log in ssh
type screen
use ssh shell
detach screen
log out

learn how to use screen