the

Little Projects

of Shawn M. Jones

This interesting set of circumstances actually exists, and quite frequently, evidently.

I recently began running Kubuntu on my laptop and started sharing the NTFS partition between Kubuntu and Windows. Unfortunately, after installing VMWare, I found out that VMWare wouldn’t start any of my virtual machines.

I was quite confused. I’d done this so many times on CentOS, I didn’t really expect Kubuntu/Ubuntu, a more user-friendly Linux distribution, to have any issues.

Well, I was wrong. It turns out that adding

mainMem.useNamedFile = "FALSE"

to the given virtual machine’s .vmx file fixes the problem.

This option forces VMWare to actually use the OS’s swap partition rather than making a swap file. Creating the swap file on NTFS seems to be an issue with NTFS on Kubuntu.

A year ago, after much consideration of differing tools, I looked at all of the open source Content Management Solutions and came to the conclusion that nothing solved every one of my needs well.

I needed the following:

1. A blog
2. A photo gallery
3. A web mail program

I tried quite a few solutions and came down to the following solutions that seemed to do their respective jobs best:

• A blog – B2Evolution
• A photo gallery – Gallery 2
• A web mail program – Squirrelmail

Then I ran into the following problems:

• No common authentication scheme for these three tools. In essence I had to log into each of them separately. This is a common problem to using multiple tools.
• A strange Out Of Memory error that occurs on my Apache web server when it runs too long. I don’t know if it’s B2 Evolution or Gallery 2 doing that. Currently the web server restarts its process every hour to avoid this (not really an optimal solution, don’t visit at the top of the hour)
• Squirrelmail has many of the features I want, but the interface is lacking.
• No way of tying the information together. I can not use the same categories for blog entries, photos, and email messages together. This was not an original requirement but became more apparent over time as I began using other tools, like Agendus on my PDA.
• PHP seems to have quite a few security holes, requiring a lot of patching/restarts of the web server.

So, with the hubris that most developers have, I decided it would be better to just write my own tools to do this.

I have looked at the following programming environments:

• Ruby on Rails – A Ruby Application Server for web development
• Zope – Like Ruby on Rails, but in Python
• J2EE – A web programming environment for Java

Each has its own pros and cons. Both Zope and Ruby on Rails appear to be very much tied to database design and relationships. J2EE is looking like a good choice for complete abstraction, but with that power comes a lot of work.

Then, there is the research needed to make certain aspects of blogs and photo galleries work.

In order to understand the implementation of Trackbacks and other Blog-related concepts, I’ll end up diving into B2Evolution’s code. In order to find out how caching is handled for photos, I’ll end up diving into Gallery 2’s code.

At that point, I might as well force those tools to do what I want.

Not all systems are synchronized to the time zone that you live in. In fact, if you rent a server like I do, it may be in an entirely different country.

CentOS has several commands concerning timezones. I don’t find some of them to be overly intuitive and figured that I would outline some easy-use recipes here:

1. Finding your system-wide timezone

The best documented way I’ve found to do this is with the following commands:

/usr/sbin/zdump /etc/localtime

You will get output like the following:

/etc/localtime  Sat Jul  5 16:42:53 2008 PDT

Which shows us that the local system-wide time zone for the server itself is “Pacific Daylight Time”.

Because we can set the time zone for our account; using the date command reveals the current time, but the wrong time zone:

# date
Sat Jul  5 19:42:53 EDT 2008

2. Setting your system-wide time zone

Setting the system-wide time zone can be achieved two ways.

One, you can copy the time zone file from /usr/share/zoneinfo to /etc/localtime.

Two, you can run the system-config-date program and choose the timezone tab. This is by far, the easiest way.

3. Setting your account time zone

Setting the account time zone is achieved by setting the TZ variable to the appropriate variable.
In Bourne Shell or BASH:

export TZ="EST5EDT"

In C-Shell or TCSH:

setenv TZ "EST5EDT"

To find out what the variable should be set to, look for the appropriate file name in /usr/share/zoneinfo or you can run the tzselect command.

4. Finding your account time zone

As noted before, running the date command shows the time zone for your environment:

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