¶ Log in to Hemera
Please open a web browser and navigate to https://hemera.rs.gsu.edu/
Please sign in with your Campus ID and Campus ID password.
Now you have access to the OnDemand.
¶ File Browser: OnDemand
OnDemand provides a simple interface to access your files through a web interface. However, it is NOT recommended to use this interface to transfer the file to and from your computer or other resources. For improved performance please use Globus provided by the ARCTIC. This interface is only intended to use as a convenient way to monitor files.
Navigate to the Files menu. File app, displayed below, allows you to view, edit existing files. also, it will allow you to create new directories, files. this app also can be used to perform lightweight file transfer operations. However for improved performance please use Globus file transfer services.
¶ Submitting workload to the clusters
ARCTIC resources use the SLURM workload management system. OnDemand provides a simplified interface where users can submit workloads to the system as SLURM jobs. Navigate to Jobs tab and select job composer.
A new tab will open with a simple job submission app.
Select a new Job and select "From default template". A new job will appear with a timestamp. However, nothing has been submitted to the system yet. We need to customize the job before submitting it to the cluster.
We need to create a resource request using SLURM commands and modify the job submission script. The app will show you the location and name of the submission script. Also, the app will provide you with options to edit the jobs submission script from the web app itself.
Hit the "Open Editor" button and the job submission script will open in a text editor in a separate tab.
Make necessary changes and save the changes. Now, the job composer should have updated content and the job is ready to submit. Now you are ready to submit the first job. Hit Submit button and the app will submit the job for you and update the status of the Job. Notice once the job is submitted to the system it will assign a job ID to the job. The system will update the status as the job progresses. In the following example, the job ID is 153974 and the job has finished successfully.
Depending on the job specification that you specify, you should see results. In the above example, Slurm has produced a job output file. slurm-153974.out. This is the standard naming convention. You can customize this with Slurm options.
Using Interactive apps
On-Demand web interface provides interactive apps, which can be used to launch some programs with GUI interfaces. Please note interactive apps are STRICTLY for DEVELOPMENT purposes. Please do not use interactive apps for production runs which runs more than 1 hour. Interactive apps are NOT designed for this purpose and you will have data losses.
In order to use interactive apps please navigate to the interactive apps menu item.
Select an interactive app. In this example, we will use ACIDs Desktop. This app starts a remote desktop on a compute node and provides you GUI via VNC connection. One an item selected it will request you to fill a few parameters before making a reservation in the system.
In the above example, It will ask you to fill, Account, Number of hours, and Number of cores. You can retrieve the account information from the Elpis management portal.
Once Launch it will wait until resources become available. Please be patient it may take some time to allocate resources
Once the resource allocation completed, you can launch the session.
Click the Launch button, it will launch noVNC session and connect you to the session within the web browser.
Once finished clicking the Delete button on the ‘My Interactive Sessions’ tab. It will terminate the remote session and release the resource.