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Allocation Year Rollover: 2018 to 2019

The NERSC 2018 Allocation Year (AY18) ends at 7:00 am on Tuesday, January 8, 2019. AY19 runs from through Monday, January 13, 2020.

Below is information related to the Allocation Year Rollover plans. All times listed are Pacific Time.

Changes at End of Allocation Year 2018

The following changes are implemented in preparation for the AY Rollover.

Premium QOS Disabled January 2-7

Beginning January 2, 2019, submissions to the premium queue on Cori and Edison will be disabled. The premium QOS will be available again when the new allocation year starts.

Account Creation/Validation Moratorium January 2-8

No user accounts will be created between Wednesday, January 2, 2019 at noon and Tuesday, January 8, 2019 at 08:00.

Moratorium on Exploratory Award Requests for AY18

Exploratory awards are small allocations made throughout the allocation year. Exploratory requests for AY2018 are no longer being accepted.

Allocation Year Rollover Process

NERSC systems will be brought down in preparation for the new allocation year. Some user jobs will be deleted, and charging for jobs will be suspended until Wednesday, January 9.

NIM System Downtime

The NIM accounting web interface will be unavailable starting at 9:00 pm on Monday January 7, 2019 and is expected to be back in service by midnight.

Web browser sessions that are active in the NIM web interface ( before the downtime must be refreshed by logging out and then logging back in, in order to display accurate information for the new allocation year.

Scheduled System Downtimes for AY Rollover

Cori and Edison will be unavailable during maintenance from 7 am to 5 pm on Tuesday January 8, 2019. After the maintenance, queued ("idle") jobs associated with non-continuing repositories will be deleted. Pending 2018 "scavenger" jobs (those in the queue that had no AY18 allocations left) will also be deleted from the queue.

Jupyter-dev will be down during the Cori maintenance from 7 am to 5 pm on Tuesday, January 8. (Jupyter will still be available).

Charging Across the Allocation Year Boundary

Charging for Allocation Year 2019 will begin on Wednesday, January 9. Jobs that run following the maintenance on Tuesday, January 8 will not be charged for the time they used on January 8.

Changes for AY19

Some major changes are in effect for AY19. NERSC has implemented a new vetting process for user accounts. Users must sign a new Appropriate Use Policy (AUP) before accessing NERSC resources. Multi-Factor Authentication (MFA) becomes mandatory for users to access NERSC resources in the majority of cases. On Edison and Cori, the default programming environments will be updated to new defaults and the SSH host keys are changing.

New Vetting Process for Users

For AY19, NERSC is implementing a new process for approving user access to NERSC resources. Some users may see a short delay between approval by their PI and access to NERSC resources. We appreciate your patience as we iron out all the wrinkles.

New Acceptable Use Policy (AUP)

The terms of the AUP and the information we collect will undergo a small change in 2019. The form is now available immediately upon login to NIM. All users must agree to the new AUP before they can use NERSC resources in AY19.

MFA Enforcement

Beginning January 8, 2019, Multi-factor authentication (MFA) for accessing NERSC systems and services will be required.  More information on MFA can be found at the NERSC MFA webpage

New Software Defaults on Cori and Edison

New Cray software environment versions from CDT/18.12 will be installed, versions from CDT/18.09 will be set to default, and old Cray software versions from CDT/18.06 will be removed on January 8, 2019. The detailed list of new versions available, new defaults, and removal list is available here. (Note: The Cray CDT [Cray Developer Toolkit] contains Cray compilers, the MPI message passing interface, performance and debugging tools, third party libraries, and other software.)

New Charge Factors on Cori and Edison

Starting on Wednesday, January 9 (any time used on the 8th is free of charge), jobs will be charged:

  • 64 NERSC hours per Edison node-hour (Edison is scheduled to retire on March 31, 2019)
  • 90 NERSC hours per Cori node-hour (KNL and Haswell alike). 

Jobs in the shared queue on Cori will be charged for a fraction of the node that they are occupying. For example, a job that ran for ten hours on 2 cores would be charged (2 cores / 32 cores/node) * 90 NERSC hours/node*hour * 10 hours = 1/16 * 90 * 10 = 56.25 NERSC hours.

Jobs Explicitly Submitted to Scavenger Queue

Jobs for which there is insufficient allocation cannot run at regular priority and belong in the scavenger (extremely low-priority) queue. Previously, these jobs would automatically be routed to the scavenger queue. Starting in AY19, jobs for which there is insufficient allocation will be rejected, and users will be required to explicitly submit to scavenger.

Held Jobs Older than 12 Weeks Will Be Deleted

Starting in AY19, any held user jobs will be deleted from the queue 12 weeks after they were submitted.

New SSH Host Keys on Cori and Edison

The SSH host keys for Cori and Edison will be changed during the maintenance. When you log back on to the systems, you will see a warning and may be prohibited from logging on due to your ssh security settings. Under normal circumstances, we would encourage users to report this security warning to us. However, due to the change in host keys, this warning is expected and does not need to be reported.

Because the host key has changed, when you try to log in to (or, which gets resolved to its own particular IP addresses, your SSH client detects that the host key is not the same as the host key for Cori (or Edison) in the known_hosts file. It may abort with output warning you of the problem, leaving it up to the user to determine if this really is Cori (or Edison), with a new identifier, or if you're being hacked.

On a Mac or Linux machine, the warning says "WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!" along with a reference to a man-in-the-middle attack and some other language designed to be alarming.

In this case, because NERSC has informed you that the host keys for Cori and Edison have changed, you can safely go into your local computer's ~/.ssh/known_hosts file and delete any lines referencing cori, edison, coriXY, edisonXY (where X and Y are integers),, or (the warning message will tell you the offending line number(s)). When you next log in to Cori (or Edison), it will be as if you're logging in for the first time, and you'll be asked to confirm the host key (by typing "yes"). You'll also need to delete lines starting with "cmom" or "edimom" in your .ssh/known_hosts file in your NERSC global home directory (for interactive jobs).

On a Windows machine using PuTTY, a window with "WARNING - POTENTIAL SECURITY BREACH!" will appear, and inform you of the differing keys. You can choose to carry on connecting and update the key by selecting "Yes", carry on connecting without updating by selecting "No", or abandon the connection by selecting "Cancel". While under normal circumstances we would recommend selecting "Cancel" and informing NERSC, since NERSC has informed you of the new Cori and Edison host keys, you can safely select "Yes".

Please see the SSH Key Fingerprints webpage on the NERSC website for the latest SSH keys.

Allocations in AY19

AY19 Allocation Awards

The AY19 allocation award letters were emailed to project PIs during the week of December 10. On January 8, 2019, the new allocations of CPU time and mass storage will be in effect. Unused allocations from AY18 do not carry over into the new allocation year, except for ALCC projects. (ALCC projects should see the remainder of their 2018/19 ALCC awards reflected in their NERSC 2019 allocation. It may take one or two days for the continuing balance to be updated on our systems. 2018/19 ALCC time expires on June 30, 2019.)

New Repositories

When a new repository is created, its initial membership consists of the PI and any PI Proxies that were designated in the ERCAP proposal. The PI and/or Proxies may add other users to the repository after the new AY starts and the repository has been activated. Instructions for adding users to repositories can be found in the "NIM User's Guide for PIs". In addition, new users may now request to have themselves added to repositories; these user initiated additions must then be approved by the PI or by a Proxy. See How to Get a NERSC Account. Users should not request accounts in new repositories until after the new AY starts.

Discontinued Users

After the new allocation year starts, a user will be considered "discontinued" if that user is not an authorized user in at least one active AY19 repository. (Note: Users in 2018 repos are not automatically authorized for 2019; a PI or PI Proxy must authorize each user for 2019.)

All discontinued users will have limited login access to their authorized systems until February 8, 2019. Such users will be unable to submit batch jobs, but will be able to perform limited interactive tasks. The intent of this access is to allow discontinued users the ability to "clean up", e.g., transfer files back to their home institution.

All discontinued users will continue to have write access to HPSS until February 8, 2019, and then read-only and delete access for six months (until August 8, 2019).