Jul 6, 2007
We're changing a lot of the systems that interoperate to provide the Library's web sites. This edition of IT Infrastructure News is a summary of those interrelated projects. Every one of these projects is complex and we can't describe every detail in a news message. So as always, let us know your questions or areas of deeper interest and we'll get back to you.
We operate a number of web servers but the majority of the content we think of as "the Library's
Web Site" is served from a machine called Cooper. Everyone who edits content on the site
knows this, and sees the published results of their changes on its web service alter ego
http://www.library.uiuc.edu/. There's a similar
server to Cooper named Coach located in the Funk ACES Library building that continually copies
content from Cooper and exists solely as an emergency spare.
Unfortunately, those two machines are showing their age (we bought them in Feb 2002) and have become increasingly unreliable. They're also running old versions of the Linux operating system and other software components. Obviously the Library's web site is a critical system, and we're not happy when it fails or can't keep up with the times.
Because of this, we've recently had to make a decision to reprioritize their migration. We
have a pre-production version of Cooper running new versions of the Linux OS, PHP 5, Apache 2.2,
mod_perl 2.0 etc. The new server is completely virtual hardware in our VMware cluster, using
SAN storage (as described in
the inaugural 5/1/2007 issue of this
newsletter). As a result of this virtualization, we will be completely retiring the Coach
The new server is currently being tested to discover and fix whatever compatibility issues result from the significant software upgrades. We expect this new server to be ready to start serving the content for www.library.uiuc.edu in the next couple weeks. This migration will not affect web page addresses (URLs), nor the method you use to edit pages. Cooper also serves the encrypted web site content for https://www-s.library.uiuc.edu/. Because of the complexities of testing and moving that site, most of which is accessed via NetID logins through "Bluestem", we plan to migrate that content to the new server more gradually.
Last fall we
recommended the creation of a
CMS implementation group. Despite that, such a team was never created. In its
absence, the Systems Office and now the IT Infrastructure & Software Development unit has
continued to work on the customization and stabilization of the OpenCms system to prepare it for
our site. This is a complex project for a complex situation, but we've made significant
Since the base system has been in active development while we work, we have been running versions 6.2.3 and 7.0 release candidates 1 & 2. OpenCms Version 7.0 final was released this week, which is what we intend to use for the production system.
We still have a lot of work to do on the system, but we plan to have it ready for a limited number of editors to start using the production system before the fall semester begins. Further development and customization will continue as the system gets used for real live pages.
We'll get more details about the CMS system and project out soon.
Another server change and project related to all of the above is the implementation of a "reverse proxy web server" that will operate in front of the other web and CMS servers. It will have no content of its own, but silently intercepts and processes all web requests coming to our sites. It essentially operates like this:
The complexity of the Library's web sites (both technically and organizationally) has brought us
to the point where a multi-tier architecture now makes sense. Most very large web sites
operate this way, since it allows a great deal of flexibility regarding the distribution of content
and processing power on the back end servers. In our case, the insertion of this additional
layer also can help reduce the impact of change on users while our content transitions to a CMS
environment. It will also allow us to bring some loose ends under the www.library.uiuc.edu
Examples of this name space improvement could be:
The front-end reverse proxy server will be deployed to full production use shortly after the Cooper migration occurs and we're sure it has worked.