1. Introduction

This document provides information you'll need to quickly begin working on Ruth. For more detailed information, see the Ruth User Guide [Not Yet Available].

2. Get a Kerberos Ticket

For security purposes, you must have a current Kerberos ticket on your computer before attempting to connect to Ruth. A Kerberos client kit must be installed on your desktop to get a Kerberos ticket. Information about installing Kerberos clients on your Windows desktop can be found on the Kerberos & Authentication page.

3. Connect to Ruth

Ruth can be accessed via Kerberized ssh as follows:

% ssh user@ruth.arl.hpc.mil

4. Home, Working, and Center-wide Directories

Each user has file space in the $HOME, $WORKDIR, and $CENTER directories. The $HOME, $WORKDIR, and $CENTER environment variables are predefined for you and point to the appropriate locations in the file systems. You are strongly encouraged to use these variables in your scripts.

Note: $WORKDIR is a "scratch" file system, and $CENTER is a center-wide file system accessible to all ARL DSRC production systems. Neither of these file systems is backed up. You are responsible for managing files in your $WORKDIR and $CENTER directories by backing up files to the archive system and deleting unneeded files. Currently, $WORKDIR files older than 30 days and $CENTER files older than 120 days are subject to being purged.

If it is determined as part of the normal purge cycle that files in your $WORKDIR directory must be deleted, we will notify you via email six days prior to deletion.

5. Transfer Files and Data to Ruth

File transfers to DSRC systems must be performed using Kerberized versions of the following tools: scp, sftp, mpscp (/usr/brl/bin/mpscp), and scampi. For example, the command below uses secure copy (scp) to copy a local file into a destination directory on a Ruth login node.

% scp local_file user@ruth.arl.hpc.mil:/target_dir

For additional information on file transfers to and from Ruth, see the File Transfers [Not Yet Available] section of the Ruth User Guide.

6. Submit Jobs to the Batch Queue

The Portable Batch System (PBS) is the workload management system for Ruth. To submit a batch job, use the following command:

sbatch [ options ] my_job_script

where my_job_script is the name of the file containing your batch script. For more information on using Slurm or job scripts, see the Ruth User Guide [Not Yet Available], the Ruth PBS Guide [Not Yet Available], or the sample script examples in the $SAMPLES_HOME directory on Ruth.

7. Batch Queues

The following table describes the queues available on Ruth:

* The limit on jobs/user in queue on the background queue is 10.

8. Monitoring Your Job

You can monitor your batch jobs on Ruth using the cqstat, qpeek, qview, or qstat commands.

The squeue command lists all jobs in the queue. The -u username option shows only jobs owned by the given user, as follows:

% qstat -u user1
                                                    Req'd  Req'd    Elap
Job ID   Username Queue    Jobname   SessID NDS TSK Memory Time  S  Time
-------- -------- -------- --------- ------ --- --- ------ ----- -  -----
1570853  user1   background tw2        --    1   1    --   12:00 R  01:12
1570854  user1   frontier   inspect    --    16  1    --   06:00 Q   --
1570939  user1   standard   45dh8      --    2   1    --   02:00 R  00:22

Notice the output contains the JobID for each job. This ID can be used with the qpeek, qview, qstat, and qdel commands.

Add the -n option to the qstat command to see all nodes that a job is running on. This option can be used in conjunction with the -u username option or with a jobID.

To delete a job, use the command qdel jobID.

To view a partially completed output file, use the qpeek jobID command.

9. Archiving Your Work

When your job is finished, you should archive any important data to prevent automatic deletion by the purge scripts.

Copy one or more files to the archive system
archive put [-C path ] [-D] [-s] file1 [file2 ...]

Copy one or more files from the archive system
archive get [-C path ] [-s] file1 [file2 ...]

For more information on archiving your files, see the ARL DSRC Archive Guide.

10. Modules

Software modules are a very convenient way to set needed environment variables and include necessary directories in your path so commands for particular applications can be found. Ruth uses modules to initialize your environment with COTS application software, system commands and libraries, compiler suites, environment variables, and PBS batch system commands.

Several modules are loaded automatically as soon as you log in. To view the currently loaded modules, use module list. To see the entire list of available modules, use module avail. You can modify the configuration of your environment by loading and unloading modules. For complete information on how to do this, see the ARL DSRC Modules Guide.

11. Available Software

A list of software on Ruth is available on the Software page.

12. Advance Reservation Service (ARS)

A subset of Ruth's nodes has been set aside for use as part of the ARS. The ARS allows users to reserve a user-designated number of nodes for a specified number of hours starting at a specific date/time. This service enables users to execute interactive or other time-critical jobs within the batch system environment. The ARS is accessible at https://reservation.hpc.mil. Authenticated access is required. For more information on ARS, see the ARS User Guide.

13. ARL HPC Portal

If you have an account on any system at a DSRC, you also have a Portal account at that DSRC. If you have an account on Ruth, you can access the system through its system and application portals on ARL's portal page. The ARL HPC Portal provides you with native web tools that allow command-line access and the ability to manage files and jobs from a web browser. The ARL HPC Portal also provides custom web applications that allow you to submit jobs from a web interface. The ARL HPC Portal supports pre/post-processing and data visualization by making DSRC hosted desktop applications that are not web-based accessible from a web browser. A training video on Using the HPC Portal is available on the PET Training website.

Ruth users are also invited to try the new refreshed look for the ARL Portal home. The new full-featured ARL Portal Home page is now available via the Enhanced App Manager page. Features include reduced tile clutter, filtering of tiles, creating favorite tiles, and a new way to manage current application sessions. Users are invited to test it and provide feedback at help@helpdesk.hpc.mil. The Legacy File Manager, Jobs, and About Me features are deprecated and will eventually be removed from all HPC Portals.

All portal accounts have a 10 GB storage quota on your portal $HOME. If your storage exceeds 10 GB, issues will occur with accessing files and applications. In order to check your storage, please use the xterm portal appliance application and run the following command: du -sh. If you have additional questions, please contact our helpdesk at dsrchelp@arl.army.mil.