FAQ's

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Screen


muarif092@raad2a:~> screen -S "my R program"
muarif092@raad2a:~> srun statement
muarif092@nid000244:~> module use /lustre..
muarif092@nid000244:~> module load R/362
muarif092@nid000244:~> Rscript mycode.R

then I press.. ctrl + a .. and then d. This will take me out of screen session and I will see message below;
[detached from 13830.my R program]
muarif092@raad2a:~>

Then I can close connection to raad2
muarif092@raad2a:~> exit

.. and later after lunch comeback login to raad2 again and issue;
muarif092@raad2a:~> screen -ls
There is a screen on:
        13830.my R program      (Detached)

muarif092@raad2a:~> screen -R "13830.my R program"
muarif092@nid00224:~>

Setup X11 forwarding

When launching a GUI based application interactively on raad2, you will have to rely on "X11 forwarding" to have the remotely executing application render its graphical interface on your local system (PC, laptop, etc). In order for this to work, the compute node launching the application needs to know the IP address of your local system, which it can fetch from the value of an environment variable called DISPLAY. In other words, you will need to set the value of DISPLAY appropriately before launching your application.

If you are using MobaXterm to access raad2, you can conveniently find the value of your DISPLAY variable by opening a local terminal (click the short tab marked with "+"). Copy the complete display variable value i.e. <IP_address>:0.0

    ┌────────────────────────────────────────────────────────────────────┐
    │             (X server, SSH client and network tools)               │
    │                                                                    │
    │ ➤ Your computer drives are accessible through the /drives path    │
    │ ➤ Your DISPLAY is set to <IP_ADDRESS>:0.0                         │
    │ ➤ When using SSH, your remote DISPLAY is automatically forwarded  │
    │ ➤ Each command status is specified by a special symbol (✔ or ✘)  │
    │                                                                    │
    └────────────────────────────────────────────────────────────────────┘

On the raad2 compute node, set the value of the DISPLAY variable as follows (of course, replace "IP_ADDRESS" with the actual address):

export DISPLAY=IP_ADDRESS:0.0