January 2008

On Thursday, January 30, 2008, we will have a scheduled downtime of the Linux public cycle servers during normal business hours.

Who is affected:

• This downtime will impact users of the 32-bit Linux cycle servers (tux, opus, and willy) and the 64-bit Linux cycle servers (soak, wash, rinse, and spin).

What is happening:

• The operating systems on these machines will be upgraded to CentOS 5.1. Note that this upgrade will take place during normal hours. We will upgrade the machines in stages (one 32-bit and one 64-bit machine at a time) to minimize disruption. Users logged in will be given a 5-minute warning before each machine is brought down. We expect that each machine will be down for less than an hour.
• Note that we will begin the upgrades at approximately 9:00am with tux and soak.

Special Note: because these upgrades involve a re-install of the operating system, crontab entries will be lost. If you have cron jobs that run on these machines, be sure to re-establish them after the upgrade.

Why it is happening:

• These upgrades address several security issues. We are upgrading them now to avoid disruption once the Spring term begins.

On Thursday, January 17, 2008, we will have a scheduled downtime from 4:00am to 8:00am EST.

Scheduled work includes:

• Upgrading virtual host web server to PHP5 (specifically, version 5.2.5)
• Install new LDAP server hardware and software
• Update the SSH server software

Why is it happening:

• The virtual host web server (virtweb) hosts websites that have URLs of the form http://[projectname].cs.princeton.edu. This server is currently running PHP4 (specifically, version 4.4.7). Because PHP4 reached its end-of-life on 12/31/07 and because there are users in the department who need PHP5, we are upgrading to version 5.2.5. For the most part, PHP code that runs on version 4 will run without change on version 5. We are contacting the owners of those project web pages that use PHP with additional information to ensure a smooth transition.
• In the not-to-distant future, we will also transition the web server that handles user home pages to PHP5. As part of this downtime, we will create a virtual host (running PHP5) that will serve the content of user public_html directories. This host will only be reachable from within the department\’s local network to let users test their home pages under PHP5 via http://web1.cs.princeton.edu/~username
• Note that user home pages will continue to be available (under PHP4) both inside and outside the department as http://www.cs.princeton.edu/~username. We have no plans to change this convention.