Changes due to Fall 2016 Maintenance Cycle

Details

Written by Super User Super User

Published: 19 December 2016 19 December 2016

Greetings Stokes users,

Stokes has returned to operation! Please remember that we have two such maintenance downtimes per year, one in late Fall (the one we just completed) and one in late Spring.

Most of what was done this cycle should not affect users. There is one change to the way unix groups are handled that users should pay particular attention to. Please take a moment to read over the changes:

Changes include the following:

1. SLURM was upgraded to version 16.05.7.
2. The latest Intel Composer (2017) and GCC (6.2.0) compilers were installed.
3. The latest OpenMPI (2.0) was built using the latest build tools (IC 2017) and GCC 6.2).
4. Repaired some of the Dell nodes.
5. The way Unix groups were handled were changed. See below for more details.

UNIX GROUP CHANGES:

Previously, each user had an account and each PI's user account had a corresponding group. Students and staff that worked with a given PI were in his or her personal group. Now it is different and works as follows:

• Every user (PI or otherwise) has his or her own group and that is one's default group. For instance, if I had a student "Tom Baker" then he would have a user account "tbaker" and a default group "tbaker".
• PIs have an additional group called pi.<PI username>. For instance, in addition to my default group "pwiegand" (in which only I am a member), I also have an account "pi.pwiegand" (in which my students and I are members). Thus, students and staff of each PI are in their own group and *also* in his or her corresponding pi group(s).
• All files in /groups/ have been grouped to "pi.<PI username>", regardless of what they were before.
• All files in /home/<user> directory have been re-grouped to each user's private group. **THIS COULD AFFECT USERS** who were using directories in their user area as a share point. We suggest that you use the shared /groups area rather than your personal user directories for this; however, if you want to still do this you must do so by changing the group to "pi.<PI Username>".

The ARCC staff appreciates your patience and thank you for your use of the resources! If you have any questions or concerns, please contact us!

Paul Wiegand & Glenn Martin

Network outage, Tue.6.Dec 1a-5a

Details

Written by R. Paul Wiegand R. Paul Wiegand

Published: 22 November 2016 22 November 2016

• outage

Due to building network maintenance beyond our control, there will be a network outage on Tuesday, December 6th from 1:00 AM to 5:00 AM. This will not affect Stokes itself, but will affect user access to Stokes during the outage.

Fall Maintenance cycle downtime, Dec.12 - Dec.19

Details

Written by R. Paul Wiegand R. Paul Wiegand

Published: 31 October 2016 31 October 2016

• downtime
• maintenance

Stokes and Newton will be taken down per our bi-annual routine maintenance cycle during Mid-December. Specifically, the clusters will be unavailable from the morning of Monday, December 12 through the morning of Monday, December 19.

Changes made during downtime will be minimal. The most significant change will be a slight change to the way groups are handled at the Linux level. We will provide more detail in the change log when we bring the system back online.

Recall that we now routinely bring the system down twice a year, once in late Fall and once in late Spring. We will keep the users notified in advance of such downtimes, but we recommend you build such expectations into your workflow. Though we anticipate no data loss during this time, it's never a bad idea to backup your materials. So we suggest you use this opportunity to copy salient data and code off of Stokes prior to the downtime.