Quick Review: Boxee Box
December 27, 2011 – 12:22 am | 3 Comments

Some of the technical issues with Boxee Box could have been fixed if the dev team was paying more attention to addressing the bugs rather than adding “features” of dubious value. In the final analysis, for the price and ease of use, Boxee Box is the best in its class and price range. You just need to be mindful of its limitations and buy it in hope of future improvements to its usability.

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Quick Review: Boxee Box
December 27, 2011 – 12:22 am | 3 Comments
Quick Review: Boxee Box

Some of the technical issues with Boxee Box could have been fixed if the dev team was paying more attention to addressing the bugs rather than adding “features” of dubious value. In the final analysis, for the price and ease of use, Boxee Box is the best in its class and price range. You just need to be mindful of its limitations and buy it in hope of future improvements to its usability.

Photo Fun with iPhone 4S
December 19, 2011 – 3:16 am | No Comment
Photo Fun with iPhone 4S

As an avid amateur photographer I would like to have my dSLR with me at all times. And my collection of lenses. And filters. And tripods. But even if this was possible, I don’t really want to be, say, sitting at a bar, looking like I just returned from a Serengeti safari. My iPhone will have to suffice and I’ll just have to get more creative with the photos apps to fill in for the fancy equipment.

Writing a Linux Startup Script
December 16, 2011 – 2:11 am | No Comment
Writing a Linux Startup Script

As basic as the task of creating a startup script may sound, even experienced sysadmins sometimes run into problems with having services start at the right time during the boot process or stop during the shutdown. Two major reasons for this: the procedure is a bit convoluted due to linking. Also, writing startup scripts is not something you have to do very often these days.

Photo Noise Reduction Apps for iPhone
December 7, 2011 – 3:59 am | No Comment
Photo Noise Reduction Apps for iPhone

In digital cameras, image noise (grain) is most pronounced in photos taken in low-light conditions without a flash. For such situations, the camera sets high ISO (light sensitivity of the image sensor) and a long exposure. A number of apps are available for the iPhone to reduce the appearance of grain. None of these apps are particularly impressive, especially when compared to specialized PC software. There is a good reason for this: digital noise reduction is a very CPU-intensive process that also requires a large amount of memory.

iPhone 4S HDR Performance
November 8, 2011 – 5:31 pm | 2 Comments
iPhone 4S HDR Performance

HDR – High Dynamic Range – photography is a method of achieving a degree of visual detail in highlights and shadows beyond what the camera’s image sensor can record in a single exposure. The HDR processing usually involves combining two or more frames taken at different exposures. This is done on the computer or inside the camera itself. Human vision uses the HDR approach.

iPhone 4S: Photo Camera Performance
October 16, 2011 – 9:46 pm | 4 Comments
iPhone 4S: Photo Camera Performance

Here’s our quick-and-dirty test of the new iPhone 4S 8-megapixel camera with LED flash and autofocus. For comparison, we took some of the same photos using a Canon G10 14.7-megapixel compact camera with a 28-140mm wide zoom lens. All photos have been corrected in Photoshop by a professional photographer to produce the best possible result for each camera. iPhone 4S was used in HDR mode.

Adding LUNs to VXVM on Linux
September 6, 2011 – 2:03 pm | One Comment
Adding LUNs to VXVM on Linux

The following is a brief overview of the process for adding LUNs to VXVM under Linux. In our example we have an RHEL 5 server with existing LUNs and VXVM volume groups. Two new LUNs with multipathing were allocated from SAN and need to be added to the system to grow one of the volumes and the corresponding filesystem.

Testing RAM in Linux
September 2, 2011 – 11:42 am | No Comment
Testing RAM in Linux

A number of good and mostly free tools are available for testing RAM hardware. However, most of these applications are designed to operate in stand-alone mode that requires shutting down the OS. Still, tare a few ways to run memory integrity checks from inside the operating environment. Here we will look at using dd and memtester.

D-Link DNS-320 NAS Review
July 10, 2011 – 6:49 pm | 2 Comments
D-Link DNS-320 NAS Review

In the past I reviewed the DNS-321 and the major complaint there was the device’s inability to utilize gigabit network capacity due to severe memory and CPU restrictions. While the DNS-321 was initially built as a 100-Mbit NAS and later converted to gigabit, the DNS-320 was built as a gigabit-capable storage device from the very beginning. It is still a very flimsy-looking plastic box filled with cheap components. If I am lucky, it may run for a year or two before the cooling fan fails or the power supply burns out.

Microsoft Launches Office 365. Fails.
June 28, 2011 – 3:47 pm | One Comment
Microsoft Launches Office 365. Fails.

To much fanfare Microsoft launched its first “cloud” version of the Office – the Office 365. Silly name, I know, but I still decided to give it a shot. Call me an optimist, but sometimes I feel there is a chance Microsoft will come out with a product more useful than Xbox 360. For the sake of brevity, let me just say that Office 365 was not that product. I can’t really tell you how good or bad it is, because I never got past the convoluted installation procedure. My many years of experience as a sysadmin did not help.

Facebook Security for the Lazy
April 28, 2011 – 2:36 am | 2 Comments
Facebook Security for the Lazy

Every time you use Facebook, you probably have a nagging feeling in the back of your head that someone other than your friends is reading your posts. You should trust that feeling. At the same time, keep in mind that Facebook is a tool designed primarily for sharing personal information with large groups of people you barely know. Facebook is not your personal diary or a substitute for SMS. You just need to assume that everything you post on Facebook inevitably will end up in the hands of someone you don’t like very much. And then you proceed based on that assumption.

Useful iPhone Apps
March 16, 2011 – 1:49 am | No Comment
Useful iPhone Apps

Useful iPhone apps? Really? Yeah, there are a few. These may not be the best-written apps, or the easiest to use, or the most aesthetically appealing, but they perform a function that benefits your bottom line. And what else can you want from computer software if not that? So let me get started in no particular order.

Don’t Be Afraid to Reboot Unix Servers
February 21, 2011 – 8:11 pm | No Comment
Don’t Be Afraid to Reboot Unix Servers

Reboot your Unix servers after making any major changes to the production environment. Should an unexpected problem come up, it will be easier to deal with it when everything is still fresh in your mind and not six months down the road, when you have to do a reboot to replace a failed system board and suddenly discover that some application wouldn’t load, by which time you forgot all about this application and have to start with the first page of the admin guide.

Converting 1080i to 720p for XBMC
January 23, 2011 – 7:22 am | No Comment
Converting 1080i to 720p for XBMC

If you are using XBMC as your video player, you might have encountered a problem playing 1080i AVCHD (*.ts or *.m2ts) videos. When playing such files, you may see just a gray screen with some …

iPhone OS 4 Upgrade: One Month Later
October 13, 2010 – 1:36 am | One Comment
iPhone OS 4 Upgrade: One Month Later

Over a month has passed since I upgraded my iPhone 3Gs to OS 4. There are a couple of significant issues that I noticed. First, the battery life – not particularly impressive to begin with – got shorter. Before I used to get through the day on one charge. I only charged my iPhone overnight. Now, in addition to the nightly charge, I find I need to use the car charger on the way from work to keep the iPhone alive. Since there have been no changes in how I use my iPhone, I have to assume OS 4 causes iPhone to consume more power.

iPhone 3GS OS4 Upgrade
September 4, 2010 – 5:23 pm | 4 Comments
iPhone 3GS OS4 Upgrade

iTunes for Windows must be one of the buggiest, most poorly written applications out there. In terms of wasted months of your life it definitely ranks up there with Lotus Notes and Media Player 12. I don’t know how well iTunes works on a Mac (I like computer mice with twenty buttons, so I never was a big Mac fan), but I think I read somewhere that iTunes for Windows is the leading cause of suicides among iPhone owners.

Gadget Review: D-Link DNS-321 NAS
August 1, 2010 – 10:51 am | One Comment
Gadget Review: D-Link DNS-321 NAS

The D-Link DNS-321 is among the least expensive dual-disk RAID NAS systems currently on the market. This small device offers an impressive array of features such as FTP, Samba, NFS, iTunes, DHCP, HTTP and UPnP …

Gadget Review: Sony PRS-900 eBook Reader
April 26, 2010 – 3:37 am | 6 Comments
Gadget Review: Sony PRS-900 eBook Reader

I have a ton of technical documentation in PDF format. Sometimes I need to browse this collection to find some specific piece of information. In other cases I may need to read an entire book …

Server and Network Monitoring with iPhone
February 25, 2010 – 6:53 pm | No Comment
Server and Network Monitoring with iPhone

What is a Unix sysadmin doing with an iPhone, you ask? It was a birthday present, if that’s all right with you. I know, I should have gotten something odd with a beta version of …

Linux and High I/O Wait
December 21, 2008 – 12:07 am | One Comment
Linux and High I/O Wait

When you look at the CPU activity of your computer, one of the parameters is the iowait. This value shows how much time your CPU wastes while it is waiting for I/O operations for complete. …

Data Security and Online Privacy
June 9, 2008 – 4:57 pm | No Comment
Data Security and Online Privacy

You have information on your computer that you don’t want others to see. Sometimes you want to share information with someone, but you don’t want anyone to know that you are the one sharing it. Let’s say that you came across some information suggesting that your employer may be breaking law. You want to make this information public, but you can’t do it openly becausloe you will be fired. Another example: you are at work and you need to send a personal, confidential email…

Effective Virus Protection
May 28, 2008 – 5:13 pm | No Comment
Effective Virus Protection

How do you protect your computer from viruses? Most computer users just buy antivirus software, install it, and reboot their PC – done. If only it was that easy. Over the past several years percentage of home and business computers infected with viruses has been steadily growing. Most PCs are sold these days with preinstalled antivirus software. And yet, the number of infected computers keeps on growing…