Hammer Upgrade to CentOS7
April 30, 2018 – June 4, 2018
This is a reminder of the upcoming maintenance next Monday and Tuesday. The downtime will be extended to 5pm Tuesday, June 5 to ensure appropriate testing is completed prior to return to service.
ORIGINAL: April 30, 2018 1:37pm
In order to continue to offer a current computational platform for CMS research at Purdue, the Hammer Community Cluster will receive an operating system upgrade to CentOS7.
Hammer is currently scheduled to be upgraded on Monday, June 4th, 2018.
Most changes are transparent for the normal CMS use of the cluster:
- The upgrade will not change how Purdue T2 users submit and do analysis via CRAB.
- Methods for SSH access and job scheduling via PBS will not change.
- Access to CVMFS and the Purdue T2 HDFS storage will not change.
However, this change will affect those users who submit jobs locally via PBS:
- Users who submit jobs to the CMS PBS queues on Hammer will need to recompile and test their codes in the new environment.
- Many system libraries will shift versions forward, and the applications, libraries, and compilers provided by Research Computing through the "module" command will all also see changes.
To provide everyone with an opportunity to test their code and applications on the new CentOS7 environment in advance, we are now opening access to a small portion of the Hammer cluster which has already been upgraded to CentOS7. If you have compiled your own applications on Hammer, we strongly urge you to recompile them for CentOS7.
To access the new test environment, log in to "hammer7.rcac.purdue.edu" via ssh. This will log you in to a CentOS7 front-end submission host. From there, you may submit to the new "hammer7" queue, which will direct your jobs to a small pool of CentOS7 nodes.
There is currently a 24-hour maximum time limit on jobs, and we ask everyone to please use this queue ONLY for testing your code and applications. Do NOT run your normal research work through this queue. This queue is very limited in size, and we want to ensure everyone has ready access to it for testing purposes.
We also have a CentOS7 login node available for interactive analysis “cms.rcac.purdue.edu”. This server is very similar to LXPLUS7 at CERN. The second login node “hep.rcac.purdue.edu” will continue to provide an environment similar to LXPLUS6 at CERN.
We are also still testing and finalizing this new environment. If you see anything missing that is necessary for your work, please email us at email@example.com so we can address it.
We hope this early access to the new environment will allow for a much smoother transition for you and your work when Hammer is fully upgraded on Monday, June 4th, 2018. Please let us know if you have any questions or concerns. Thank you!