Date: Tuesday, June 2nd, 2026 (09:00-10:30)

Who is affected:
Anything physically connected to the CS building network in the offices and
open areas. Please note, this will not impact wireless connectivity or any
of the equipment in room 002.

What is happening:
We will be upgrading the firmware on our network switches in room 218. This
action will result in a brief network outage of approximately 3 minutes in
each respective location. This upgrade will be conducted one switch at a
time to both reduce risk and only cause brief isolated outages.

Why is it happening:
The firmware on these switches is in need of an upgrade in order to patch
for security issues, bugs, and to implement new features on our network
switches for future projects.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Date: Wednesday, May 27, 2026 (7:00-9:00)

Who is affected:
All users of the CS Department publicdb database server, including any
dependent web properties and all CS Department Beowulf high-performance
computing cluster users, known as ionic and neuronic.

All users of CS Department administrative web properties (Dropbox, CS
Guide, the Main website, etc.)

What is happening:
During this window, the publicdb database server will be upgraded to the
latest Redhat distribution. No data loss is anticipated. However, while
Slurm jobs will continue, new jobs cannot start during the migration.

In addition, the database server underlying the administrative systems will
be upgraded. During the upgrade, all database-dependent administrative
systems will be unavailable. This includes the CS Dropbox service, the main
website, the CS Guide, ADM, and any content feeds provided by CS Staff.

Why is it happening:
publicdb database server MariaDB will be upgraded from 10.5.22 to 10.5.29.

phpMyadmin web interface will be upgraded from version 5.2.1 to 5.2.3.

This is part of regular maintenance to enhance system performance and
security.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Date: Tuesday, June 9, 2026 (06:00-18:00)

Who is affected:
ALL users of CS Department (or University) cluster computing systems
AND
ALL users of research rack space at the HPCRC (151 Forrestal Road)

What is happening:
On June 9, 2026, all “A”-side power at the HPCRC will be turned off and
unavailable for the full business day while preventative major maintenance
is performed on the building’s power systems. “A”-side power accounts for
half the power to the building, and ALL of the power to most racks occupied
by the Computer Science Department.

ALL researchers with equipment in HPCRC racks should anticipate that they
will lose power at 07:00 and not regain power before 15:00. It is
recommended that researchers arrange to power off their equipment prior to
the 07:00 start time and be prepared to check its health and restore
services after the 15:00 end. CS Staff is announcing a wider 12-hour window
to allow for this time to orderly shut down clusters, and to power back on
after the work.

ALL ionic and neuronic cluster resources will be offline and unavailable.
ALL courselab and armlab systems will be offline and unavailable.
The “cycles” systems will be rebooted at the start of the window, but are
anticipated to be available.
All other central CS services (e.g. email, web service, storage) are
anticipated to remain available.

OIT’s announcement of this maintenance can be found here:
oit.princeton.edu/events/hpcrc-planned-downtime-maintenance

Why is it happening:
The power equipment at the HPCRC is overdue for major maintenance to reduce
the risk of unplanned failures and outages. This maintenance window, and a
related upcoming outage on October 20, will allow for this maintenance to
be performed safely.

The October 20 outage will be announced separately later in the Summer and
will be essentially identical to this one, but affecting the “B”-side
power.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Hello, everyone.

This is a reminder that we are one week away from the CS Cycles/Ionic/Neuronic Systems downtime.

Thank you,
CS Staff

—– Forwarded Message —–
From: csstaff@cs.princeton.edu
To: downtime@lists.cs.princeton.edu
Sent: Tuesday, December 16, 2025 9:05:04 AM
Subject: [downtime] CS Cycles/Ionic/Neuronic Systems Downtime, Tuesday, January 13, 2026, 07:00-15:00

Date: Tuesday, January 13, 2026 (07:00-15:00)

Who is affected:
All users of the CS Department Beowulf high performance computing clusters,
known as ionic and neuronic.

All users of the CS Staff-managed public login systems, including the
cycles, courselab, and armlab systems.

What is happening:
CS Staff will upgrade the Ionic and Neuronic clusters, as well as the
Cycles, Courselab, and Armlab systems, to the latest Red Hat 9
distribution.

In addition, the cluster management and job scheduling system, Slurm, along
with its database, will also be upgraded. No data loss is anticipated.

Why is it happening:
This is part of the routine maintenance and will bring newer versions of
installed tools and software.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Date: Tuesday, January 13, 2026 (07:00-15:00)

Who is affected:
All users of the CS Department Beowulf high performance computing clusters,
known as ionic and neuronic.

All users of the CS Staff-managed public login systems, including the
cycles, courselab, and armlab systems.

What is happening:
CS Staff will upgrade the Ionic and Neuronic clusters, as well as the
Cycles, Courselab, and Armlab systems, to the latest Red Hat 9
distribution.

In addition, the cluster management and job scheduling system, Slurm, along
with its database, will also be upgraded. No data loss is anticipated.

Why is it happening:
This is part of the routine maintenance and will bring newer versions of
installed tools and software.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Hello, everyone.

In order to accommodate several research and conference deadlines that were brought to our attention, we have adjusted the maintenance window to Wednesday, November 19 at 5:00 am.

Thank you,
CS Staff

—– Original Message —–
From: csstaff@cs.princeton.edu
To: downtime@lists.cs.princeton.edu
Sent: Monday, November 3, 2025 9:24:13 AM
Subject: [downtime] CS Storage Maintenance, Wednesday, November 12, 2025, 09:00-15:00

Date: Wednesday, November 12, 2025 (09:00-15:00)

Who is affected:
All users of the CS department storage or computing facilities.

What is happening:
We are upgrading our storage operating system, which requires the
components of the CS storage system to be rebooted. This upgrade is
expected to be mostly non-disruptive, and department services will continue
as usual, but sporadic moments of interruption may be noticeable at times.

All services that depend upon access to storage share the same minor risk
of performance hiccups for some periods during this window, including cycle
servers, ionic and neuronic clusters, web content, home directories, CIFS,
etc.

Why is it happening:
In July, we identified that a filesystem bug affecting critical shared
storage was causing intermittent failures of some of our web services. This
problem, which occasionally restricted required access and disrupted site
availability, and had no viable workaround, has been under review while we
awaited an official fix from Dell. During the upcoming upgrade, we will
apply the newly released OneFS patch to resolve this issue and enhance
overall service reliability.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Date: Wednesday, November 12, 2025 (09:00-15:00)

Who is affected:
All users of the CS department storage or computing facilities.

What is happening:
We are upgrading our storage operating system, which requires the
components of the CS storage system to be rebooted. This upgrade is
expected to be mostly non-disruptive, and department services will continue
as usual, but sporadic moments of interruption may be noticeable at times.

All services that depend upon access to storage share the same minor risk
of performance hiccups for some periods during this window, including cycle
servers, ionic and neuronic clusters, web content, home directories, CIFS,
etc.

Why is it happening:
In July, we identified that a filesystem bug affecting critical shared
storage was causing intermittent failures of some of our web services. This
problem, which occasionally restricted required access and disrupted site
availability, and had no viable workaround, has been under review while we
awaited an official fix from Dell. During the upcoming upgrade, we will
apply the newly released OneFS patch to resolve this issue and enhance
overall service reliability.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Date: Tuesday, August 5, 2025 (06:00-11:00)

Who is affected:
All users of the CS department storage or computing facilities.

What is happening:
We are upgrading our storage operating system, which requires the
components of the CS storage system to be rebooted. This upgrade is
expected to be mostly non-disruptive, and department services will continue
as usual, but sporadic moments of interruption may be noticeable at times.

All services that depend upon access to storage share the same minor risk
of performance hiccups for some periods during this window, including cycle
servers, ionic and neuronic clusters, web content, home directories, CIFS,
etc.

Why is it happening:
An upgrade is required to address a bug that is causing unreliable snapshot
expiration, generating unnecessary costs.

While we do not anticipate any extended service outages, you may find that
there are momentary interruptions, and some connections (especially
CIFS/SMB connections) may need to be reestablished.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Date: Tuesday, July 15, 2025 (07:00-15:00)

Who is affected:
All users of the CS Department Beowulf high performance computing clusters,
known as ionic and neuronic.

All users of the CS Staff-managed public login systems, including the
cycles, courselab, and armlab systems.

What is happening:
CS Staff will upgrade the Ionic and Neuronic clusters, as well as the
Cycles, Courselab, and Armlab systems, to the latest Red Hat 9
distribution.

In addition, the cluster management and job scheduling system, Slurm, along
with its database, will also be upgraded. No data loss is anticipated.

Why is it happening:
This is part of the routine maintenance and will bring newer versions of
installed tools and software.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff

Date: Tuesday, July 1, 2025 (06:00-16:00)

Who is affected:
All users of the CS department storage or computing facilities.

What is happening:
We are upgrading our storage operating system, which requires the
components of the CS storage system to be rebooted. This upgrade is
expected to be mostly non-disruptive, and department services will continue
as usual, but sporadic moments of interruption may be noticeable at times.

All services that depend upon access to storage share the same minor risk
of performance hiccups for some periods during this window, including cycle
servers, ionic and neuronic clusters, web content, home directories, CIFS,
etc.

Why is it happening:
Our current operating system has reached end-of-life status and needs an
upgrade.

While we do not anticipate any extended service outages, you may find that
there are momentary interruptions, and some connections (especially
CIFS/SMB connections) may need to be reestablished.

We will post updates to the status page: www.csstaff.org
as necessary.

If this downtime will cause you undue hardship, please contact
csstaff@cs.princeton.edu immediately, so we can discuss options to reduce
any negative impact. Your patience is appreciated.

Sincerely,
CS Staff