In a classroom or lab environment, it is easy to create non-typical situations and cause RHEL5 Linux to behave badly. Such was the case over the past week for one of my personal lab servers. The server is stand alone and does not belong to a domain. It is not configured as a DNS or DHCP server at the present time.

A couple of weeks ago I was configuring Samba on the server in question. After I was finished with the configuration change, I noticed it took this box a really long time to boot up. The boot sequence hung on sendmail. Once the server was up and running, xorg X server was very slow and sluggish. I could not get a gnome-terminal to open at all. Using a virtual console or a remote ssh shell was no problem.

After days of on and off head scratching, and more than one Google search, I finally realized that I had changed the hostname on this server in the /etc/sysconfig/network file, but NOT in the local /etc/hosts file. Since the hostname was not included in any DNS zone file, some services that needed to resolve the hostname to an IP address were very unhappy. By simply adding the new hostname to the 127.0.0.1 line in the /etc/hosts file everything started working fine again.

I am sharing this insight with the hope that other RHEL5 administrators will be able to save some time if this happens to them.

The Information Technology Departments in the Business/Public Service Division at Greenville Technical College where I teach subscribe to the MSDN Academic Alliance which provides our students and faculty free download versions of select Microsoft products. Starting in September 2009, we were able to download either the 32-bit or 64-bit versions of Windows 7 Professional. Jumping on the opportunity to install Microsoft's latest operating system and move from 32-bit to a 64-bit data path, the week of October 12, 2009 I began migrating from Windows XP Professional Service Pack 3 to the new Windows 7 Professional.

Before starting the migration project, I had several concerns:

• Would the 64-bit version of Windows 7 have a driver for the ATI SB600 SATA RAID controller on my MSI K9AGM motherboard which I am using for a RAID1 array?
• Could I dual boot between 32-bit Windows XP and 64-bit Windows 7?
• Would the 64-bit version of Windows 7 have a driver for my EVGA Nvidia 8600 GT video card?

As a budget cutback, our school administrators asked us to shutdown all non-essential classroom computers at night to save electricity. I teach Linux in a classroom that has a Dell Poweredge 2850 Red Hat Enterprise Linux (RHEL5) server and 29 Dell Optiplex 745 student lab computers running Microsoft Windows XP SP3 as the host operating system and VMWare Server to provide virtual Linux machines for our classes. I researched on the Internet for the best solution to remotely shutdown the student lab computers at night. I was not able to find one post or how-to that completely answered my questions, but I was able to piece together a solution. In an effort to document this project and help others with similar needs, here are my notes on the project:

The following is taken from recent posts I made to http://www.howtoforge.com/forums/showthread.php?t=27297:

In a recent installation of RHEL5.2, SELinux is blocking Webalizer from writing stats to /var/www/html/sitename/stats. What is the best way to remedy this issue short of disabling SELinux? This is a default installation, very little customization at this point.

For the last three hours I have been working on a project to install Microsoft Windows 7 Beta on an external hard drive. My goal is to create a portable installation that I can use on various computers in order to demonstrate the latest operating system offering from Microsoft to students.

The following are my notes from this project:

Thanks to my friend Stoo Potts for forwarding this presentation. It is well worth your time to watch the whole presentation, maybe more than once.

Click this link to view "Technology: Did you know?"

 After 25 years of drying clothes and constant clogging with lint, it became apparent to Sharon and I that it was time to replace the old plastic accordion type dryer vent pipe with something more safe and durable. Our dryer had started overheating and turning itself off to keep from starting a fire, all due to a clogged vent pipe. A couple of years ago we paid a local home repair company about $500 to unclog the old pipe. They managed to punch holes in the old plastic pipe and could not clean out the whole length because of turns around corners. This time we decided to fix the problem properly. We hired a local general contractor to coordinate a week long renovation project.