Derecho and Casper resources will undergo maintenance on Tuesday, November 5th from approximately 7am-8pm. JupyterHub, Derecho, and Casper login and compute nodes will be unavailable for the full duration of this time window, and Quasar will be down for approximately 2 hours.
The primary maintenance activity will be to update GLADE file system client software on all Derecho and Casper components. This is a critical upgrade required to mitigate a very rare but potentially impactful bug. We will also update the operating system on some backend components of Casper (with no user-facing impacts), and complete a small amount of network re–cabling work.
As typical, scheduler reservations will be put in place across the systems to ensure that all user jobs have completed by 7:00 AM November 5th as the downtime begins. Any jobs that are queued on Derecho and Casper when the downtime begins will be retained for execution when the systems return to service.
