[downtime] Public Login Machines tux and opus Will Be Retired August 1, 2016

Date: August 1, 2016

Who is affected:
All users of the CS Department public login hosts, tux.cs.princeton.edu and
opus.cs.princeton.edu (penguins.cs.princeton.edu).

What is happening:
On August 1, 2016, tux and opus will be turned off and retired. Future
logins should use cycles.cs.princeton.edu (soak, wash, rinse, or spin).

NOTE: As these servers are retiring, all crontabs on tux and opus will be
retired with them. If you need to maintain a crontab currently active on
one of these systems, you will need to relocate it to one of the cycles
machines before August 1.

The DNS names “tux”, “opus”, and “penguins” will all remain for a period of
at least six months, and will become aliases for “cycles.cs.princeton.edu”.
We encourage you to use the time to update your scripts, configurations, or
other references to the retiring names.

Why is it happening:
The purpose of tux and opus, for the last several years, has been to
provide a space for lightweight interactive work such as reading email or
organizing files. This was specifically intended to separate these
interactive activities from the more computationally intensive work done on
the cycles servers, so as to reduce the incidence of conflict.

In recent years, advances in kernel technology and our configuration
management systems have enabled us to provide a more stable and fair
environment in the cycles servers such that most users can maintain a
reasonable share of system resources, even while other users are doing
computationally intensive work. For this reason, the separation of the
penguins servers is no longer as useful as it once was, and the costs of
maintaining the distinct system configurations (as well as user confusion
resulting in computationally intensive work running on penguins) has risen
enough to outweigh the benefits.

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

If this system retirement 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.