Virtual Environments for Collaborative Visualization and Experimentation.

Josh's blog

per user web directories in Apache 2

Posted Mon, 08/16/2010 - 17:25 by Josh

The default Apache 2 installation on Ubuntu 10.04  Provides one web root directory which is located in /var/www to provide additional webroot directories it is necessary to alter the default configuration file located in /etc/Apache/sites-available

In the case of providing multiple users access to different web root accounts that work with Apache 2 the developers at Apache foundation created a directive called UserDir.  This directive allows the system administrator to specify which directory within each users home directory to look for HTML documents. It can also be used to enable or deny access to specific users based on username. It is often used to disable the root user's web directory for security purposes.

Squid - caching proxy

Posted Mon, 07/19/2010 - 00:36 by Josh

{s q u i d}Squid is a FOSS project that was started with an NSF grant and has continued with the support of volunteers, donors, and commercial support.  I am currently testing it on a small lab network to see if I can notice a difference in web surfing speed.  I learned of squid when I was reading an article in Communications of the ACM about a caching proxy called Varnish.  The author, a kernel developer on the FreeBSD project, claimed to have created a caching proxy that was ten times faster than the highest performing proxy caching servers. Squid is such a high performance caching proxy and his remarks were clearly a reference to squid.  

Strong Passwords: A first defense against intrusion.

Posted Sun, 06/20/2010 - 13:13 by Josh

The Password.

A lock on your door or a safe at the bank are there for a good reason, they protect property from theives. The passwords on a system are there for the same reason. Using a weak password is the equivalent of having no password at all because anyone can download and use a variety of freely available tools to crack your password while simultaneously hiding their location. A system that uses a weak password is like a bank that keeps all thier cash on a pallet by the front door. (continued)

Sun Ray 3 Plus for High Resolution Desktop Virtualization

Posted Tue, 06/08/2010 - 12:26 by Josh

The newest SunRay from Oracle/Sun.

On March 31st Oracle announced the release of the next generation of Sun Ray thin client device. The new machine has far superior graphics abilities and Gigabit Ethernet ports and fiber optic ports.  Yet it still consumes only 15 watts.  My desktop uses something like 400 watts. 

To the chagrin of it's users the SunRay 2 client only supported USB 1.1, but users will be happy to know that the newest SunRay does support USB 2.0 on all 4 of its USB ports. Very nice.

Realtime Worlds' MMO: APB --->Unreal Engine 3 + Vivox

Posted Sat, 06/05/2010 - 11:33 by Josh

<--[realtime worlds]-->Realtime Worlds was founded in 2002. It's headquarters are in Boulder, Colorado and it's developement offices are in Dundee Scotland. They have assembled a team of professionals that have worked on such titles as "Crackdown","Lemmings", and "Grand Theft Auto".

Players are immersed in 3D positional audio from Vivox, (this is what Linden Labs and IBM use for their audio). Absent a headset they can still chat with a keyboard. In order to give players a good visual experience and natural character movement AFB uses Unreal Engine 3, perhaps the best physics engine available.

Oracle VM - Part II

Posted Fri, 06/04/2010 - 14:22 by Josh

When the need for virtualization became very apparent in our server room I did many hours of research. From marketing materials and official documentation to Wiki and blog posts I looked over the alternatives. Of primary importance? Ease of use, efficiency and ubiquity. I don't want a solution that is difficult to use and undocumented. Obviously it must provide efficient use of the hardware. I want something that is useful on my resume as well. If I choose something unheard of, well what use it to me?

Budget Cold Aisle Containment with Vinyl

Posted Wed, 05/19/2010 - 22:06 by Josh

Google's low cost containment solution shows that modular data center curtains can go a long way in separating hot and cold isles in a data center.  Some claim 20 percent reduction in cooling costs and over sixty percent reduction in energy used by fans. Trax and Simplex both offer a variety of low cost solutions using curtains and hardwall enclosures.