UMD Facilities has informed us with a limited lead time notification that they must take an emergency chilled water outage to repair the pumps that support the air conditioning and humidification in our AVW data center. Facilities are requiring up to a 3 day window that will start in the early morning of August 21st 2026. We will have very limited spot temperature control during this window which will require us to shut down the Nexus[0] cluster for the duration of this work. All pending Nexus SLURM jobs will be held in queue during this period. Other web based services and the Object Store will available during this window.

Since we have a maintenance window the night before the start of this work we will be shutting down the Nexus cluster after our maintenance window and have extended the SLURM outage reservation. The Technical Staff will restore access to Nexus as soon as Facilities gives us the all clear on the repair work and the room has returned to an operational status to support the Nexus cluster.

UMIACS and CMNS had requested this be delayed further into the fall to allow us to better plan and inform our users of this outage. After review at the Vice President level it was decided to go ahead with this outage even with the limited lead time for notification.

Thanks,
–UMIACS Technical Staff

[0] - https://wiki.umiacs.umd.edu/umiacs/index.php/Nexus