Frequently asked questions (FAQ) on SSG and SDS

What is the distinction between SSG and SDS?

The Social Science Gateway (SSG) is a general purpose compute cluster, tied to the XSEDE, and focussed on providing SAS, Stata, and (potentially) SPSS to users who do not have access to such resources “close” to TeraGrid resources. It also provides compute resources to the core VirtualRDC constituency, i.e., users who are preparing data access request to the Census Bureau’s Research Data Centers, and those who wish to use innovative full-access synthetic data sets. To request access to the SSG, please go here: http://www.vrdc.cornell.edu/news/social-science-gateway/step-1-requesting-a-ssg-account/. To learn more on how to use it, please see our SSG –  Step 4 page.

The Synthetic Data Server (SDS) is a custom compute server dedicated to providing structured access to early-access releases of innovative synthetic data. Data is provided by the Census Bureau, and the server is set up to closely replicate the structure of equivalent restricted-access compute servers housing confidential data within the U.S. Census Bureau. The SDS itself does not house any confidential data – all data has been vetted for release.

Where is the SIPP Synthetic Beta or the Synthetic LBD v2 on SSG?

In order to gain access to the SDS, you also get an account on the SSG, but you cannot access the specific data that the SDS houses through the SSG cluster. Please login to the SDS to access that data.

How do I request help?

• For help with the SSG, please email Ssg-help@cac.cornell.edu.
• For help with the SDS, please email Sds-help@cac.cornell.edu. Issues regarding the server itself (software, access), Cornell will address your issue. For issues with the data, your request will be forwarded to the relevant contacts at the Census Bureau (or you can email them directly).

How do I run SAS/Stata/R on SSG?

In general, you need to either submit a request for an interactive job to the compute nodes (iqsub) or submit a longer-running job to the queue, using qsas, qstata, or a custom qsub job.

(On SDS, this is not necessary).

For interactive (GUI) SAS, you should simply be able to select “SAS” from the KDE or Gnome menu.

I’m having trouble installing the NX config file on Mac OS X

NX stores its config files in /Users/username/.nx/. Because the folder name begins with a period, the Mac OS X Finder hides that folder, making it difficult to put the required NX config files provided by the SSG and SDS into that folder.

SSG users have used  Path Finder (http://cocoatech.com/) to place the .nxs file in the proper folder. Path Finder is free for 30 days and the current version works in Mac OS X 10.5 and 10.6. Open Path Finder and navigate to the user folder. Its contents should look just like they do in the Mac OS X Finder, with folders such as Downloads, Documents, Library, etc. Now, select “Show Invisible Files” from the View menu. Some files and folders beginning with “.” will now appear in the user folder. Open .nx, then the config folder inside of .nx, and place the .nxs file within the config folder. The NX Client will see this config file the next time it is launched. (thanks to Chris Handy for providing this information)

Cut-and-paste not working on NX for Mac OS X

NX for Mac OS X uses the X11 layer, so it runs somewhat like an application within another application. Users may encounter cut-and-paste problems. At least one user found the solution as follows: “the X 11 pasteboard preference has an enable syncing button. When I unchecked this  button I was able to cut and paste within an application. Problem solved.” (thanks to Peter Gottschalk for this information)

Forgot password/account locked/my cat ate the paper with my password

Common causes of locked accounts, “failed authentication” responses in NX, and their solutions are:

• Mistyping your password several times in a row.
  Solution: Wait about a 1/2 hour and then try again. Be sure that your caps lock key is not on!
• Trying to login via NX  when you have a new or expired password (you get a “authentication failed” message even if you are sure that it is the right password).
  Solution: Login using SSH (see Step2). Passwords expire after a certain period. NX login facility does not have the ability to prompt you to change your password.
• If you can log in via SSH, but NX is still not working: Clean out the cache on the server side. Instructions here are for command line, but you can use a file system browser as well:
  • from SSH, type cd .nx (notice the dot in front of nx.
  • type ls. You should see a couple of directories that include the word “cache”, and directory names that have a capital “C” at the start. You will delete them all (don’t worry, they get recreated). Example: cache-gnome or C-ssg.vrdc.cornell.edu-1234-FB42A24CF24D7214B1A6109EFC104D2B
  • type rm -rf cache* C-ssg*

  Now try to log in again with NX.

• If all fails, request a password reset by from the appropriate email help address, referencing your login ID. You will then also have to log in using SSH (see Step2).

Unsubscribing from listserv

You are automatically signed up to listservs notifying you of issues with the servers. Emails will be sent to the email address that you originally specified when signing up for access. If at any time you wish to unsubscribe from the listserv, follow instructions at http://www2.cit.cornell.edu/computer/elist/lyris/leave.html