From Cheaha
Revision as of 20:42, 16 April 2014 by (talk | contribs) (→‎No Backups!: Fix typos and slang)
Jump to navigation Jump to search

Attention: Research Computing Documentation has Moved

Please use the new documentation url for all Research Computing documentation needs.

As a result of this move, we have deprecated use of this wiki for documentation. We are providing read-only access to the content to facilitate migration of bookmarks and to serve as an historical record. All content updates should be made at the new documentation site. The original wiki will not receive further updates.

Thank you,

The Research Computing Team

Research Storage provides versatile containers for your data sets. The containers include dedicated space available on the Cheaha HPC platform.

What do I get

Each active user on Cheaha receives an annual 1-terabyte allocation of Research Storage at no direct cost to the user. This container is dedicated to your storage needs and is attached directly to the cluster.

Additional storage capacity can purchased, see details below.

How to get it

Once you log in to Cheaha, you can access your default 1TB storage container here:

 cd /rstore/user/$USER/default

You can check to see how much storage you have used in your container with the command:

 df -h /rstore/user/$USER/default

How to use it

For HPC work flows

You can use this storage in any way that you find useful to assist you with your HPC work flows on Cheaha.

You should still follow good high performance compute work flow recommendations and stage data sets $USER_SCRATCH during your job runs, especially if those data sets are heavily accessed or modified as part of your job operations.

In general, a good use this storage for keeping larger data sets on the cluster longer than the lifetime of your active computations and for stuff that is too big to fit in your home directory.

For Retaining Scratch Data

One near term use for your storage container would be to safely preserve important data in your $USER_SCRATCH so that it is not destroyed by the upcoming scratch file system rebuild during the May 3-10 cluster service window.

You can follow these steps to move a copy of important files from your personal scratch space to your default Research Storage container:

  1. Remove any data from $USER_SCRATCH that you no longer use or want
  2. Copy your remaining important data to your default container using rsync
  rsync -a --stats $USER_SCRATCH/ /rstore/user/$USER/default/scratch

How to get more

You can buy any amount of additional storage at a rate of $0.38/Gigabyte/year. That's $395/Terabyte/year. All we need to know is how much storage you want, for how long, and an account number. UAB IT will bill you monthly for the storage you consume

What about backups?

No Backups!

There is no central back up process on the cluster. Each user is responsible for backing up their own data. If you are not managing a back up process for data on the cluster then you do not have any back ups.

This rule includes the new Research Storage containers.

Please understand we do not say this out of malice or a lack of concern for your data. Central backup processes are inherently ignorant and must assume all files are important. This is done at the very real expense of keeping multiple copies of data. In the context of large scale data sets which are typical of our HPC environment, this would amount to 100's of terabytes of data. Duplicating the footprint of data for which we are already bursting at the seams to support a single copy.

It is much better for individuals, teams, or labs and their technical support staff to identify critical data and ensure it is backed up.

How to Backup

We understand this process can be difficult, especially if you are your own technical support staff.

To that end, we have a new backup service available that leverages CrashPlan, a popular commercial backup product that will help you easily back up your data on your laptop or in your lab.

Please contact us if you are interested in using CrashPlan to fulfil your responsibilities for backing up your own data.