Send process to a node in background and logout

horacioemilio · 12-13-2007, 08:11 AM

Hi, I am trying to get a script running out which sends jobs to a list of nodes like the following;

Code:

#!/bin/bash


for i in `seq $1 $2`
do
        # 1. create directory with the right name 
        #    taking into account possible different rounds of jobs
        rm -fr job_node$i
        mkdir job_node$i
        cp -r /some_funny_folder_base_files job_node$i

        # 3. launch the job on this node
        echo " cd /somepath/job_node$i/1st_run; nohup ./run.exe inputfile &"  | ssh node$i     
        
done

but the problem is that is stops on the first node an the output of the program on the screen. If I manually log onto each node and send the calculation using

Code:

nohup ./run.exe inputfile &

then the program starts to run and I can logout withhout problems.

So what should I do to leave the programs running on each node with this script or some other solution ?

thanks

unSpawn · 12-13-2007, 03:10 PM

How about executing the command on multiple servers at the same time using something like ClusterSSH instead?

horacioemilio · 12-14-2007, 04:58 AM

it would be interesting but in this machine i can not install anything

Quote:

Originally Posted by unSpawn

How about executing the command on multiple servers at the same time using something like ClusterSSH instead?

tronayne · 12-14-2007, 06:36 AM

I think you may need to launch your child process(es) like this

Code:

...
nohup ./run.exe inputfile >> /dev/null 2>>/dev/null &
...

That is, without piping the output of the parent or run.exe into ssh in the parent process -- do the pipe in run.exe instead, passing any necessary arguments to it from the parent

Code:

...
nohup ./run.exe ${ARG1} ${ARG2} inputfile >> /dev/null 2>>/dev/null &
...

You need to handle your output to ssh or any log files in run.exe.

We use the above method to launch-and-forget a long-running application; the user executes the parent which launches the child, logs off and goes home. Bear in mind too that the child inherits the environment from the parent but it's not a bad idea to make any required environment settings in the child just to make sure.

Hope this helps some.

horacioemilio · 12-14-2007, 12:59 PM

it worked !

thanks

Quote:

Originally Posted by tronayne

I think you may need to launch your child process(es) like this

Code:

...
nohup ./run.exe inputfile >> /dev/null 2>>/dev/null &
...

That is, without piping the output of the parent or run.exe into ssh in the parent process -- do the pipe in run.exe instead, passing any necessary arguments to it from the parent

Code:

...
nohup ./run.exe ${ARG1} ${ARG2} inputfile >> /dev/null 2>>/dev/null &
...

You need to handle your output to ssh or any log files in run.exe.

We use the above method to launch-and-forget a long-running application; the user executes the parent which launches the child, logs off and goes home. Bear in mind too that the child inherits the environment from the parent but it's not a bad idea to make any required environment settings in the child just to make sure.

Hope this helps some.