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April 16, 2013 – 12:39 pm |

Imagine you have an HPC cluster with a hundred compute nodes named node001-node100. The two commands below will help you generate a list of node names – either all name on one line or one name per …

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Articles in Hardware

iPhone Stopped Syncing with Google Calendar

April 3, 2013 – 3:05 pm |

A small but potentially annoying problem: on rare occasions, your iPhone/iPad may decide your calendar looks full enough and will stop syncing with your Google calendar. This is a situation where:

Calendar sync between your iDevice and …

Quick Review: Boxee Box

December 27, 2011 – 12:22 am | 10 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 | 3 Comments
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.

Disable Usage Information Sharing on iPhone

December 19, 2011 – 1:23 am | 8 Comments
Disable Usage Information Sharing on iPhone

Carrier IQ is software installed on your iPhone by Apple at the request of the service providers. This system utility collect detailed usage and location data on your phone and sends it to the service providers. Supposedly, this was done to improve quality of service. In reality, however, if any such improvement actually occurred, it was only a side-effect.

Photo Noise Reduction Apps for iPhone

December 7, 2011 – 3:59 am | 22 Comments
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 | 7 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.

Fun with Call Forwarding

October 31, 2011 – 10:20 pm | 8 Comments
Fun with Call Forwarding

Sometimes you don’t want people to reach you on your phone, but you don’t want to do something obvious, like turning the phone off. Because then they’ll just leave you a message and you will still be expected to call back. Below is a list of phone number in various US area codes that you can use to forward your unwanted calls.

iPhone 4S: Photo Camera Performance

October 16, 2011 – 9:46 pm | 6 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.

Enable Foreign Keyboard on iPhone

August 16, 2011 – 1:38 pm | 5 Comments
Enable Foreign Keyboard on iPhone

This is a simple one, but people are always asking: how do I type in Russian, Swedish, Spanish, whatever on my iPhone? Go to Settings -> General -> International -> Keyboards -> Add New Keyboard -> select your language -> select Hardware Keyboard Layout (if applicable).

D-Link DNS-320 NAS Review

July 10, 2011 – 6:49 pm | 53 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.

iPhone OS 4 Upgrade: One Month Later

October 13, 2010 – 1:36 am | 2 Comments
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 | 5 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 | 7 Comments
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 | 12 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 | 8 Comments
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 …

Building a Home Theater Computer

December 24, 2009 – 7:23 am | 10 Comments
Building a Home Theater Computer

Ever wanted to build a kick-ass home theater computer? Here we have some highly detailed instructions for putting together just such a device. It is not a DVR like TiVo or your Verizon HDTV box. …

Working with Linux Driver Modules

December 22, 2009 – 6:57 pm | 2 Comments
Working with Linux Driver Modules

You just replaced a failed network card, rebooted your server and now network wouldn’t start and your screen is filled with cryptic error messages about some kernel module doing something it’s not supposed to do. …

Printing from SuSE/SLES to a Windows Printer

December 10, 2009 – 5:05 pm | 3 Comments
Printing from SuSE/SLES to a Windows Printer

The following document explains how to configure your SuSE or SLES system to be able to print to a remote printer shared from a Windows server. The first step is to install Unix print support …

iPhone Photography: Making Photos Better

September 17, 2009 – 9:05 pm | 4 Comments
iPhone Photography: Making Photos Better

The is the first installment of the three-part review of the better photo apps for iPhone. In the follow-up reviews we will look at artistic photo filters and panorama applications. If you don’t want to …

Great iPhone Apps

September 3, 2009 – 3:22 am | 4 Comments
Great iPhone Apps

After spending hundreds of dollars at the iPhone app store and writing many negative reviews, I believe I finally stumbled upon a few applications warranting a positive reaction. Back in June Apple was bragging …

More Bad iPhone Apps

August 13, 2009 – 1:19 am | 4 Comments
More Bad iPhone Apps

This is the second part of my review of iPhone apps unworthy of your ninety nine cents. You can read the first part here.
Certain applications are well-written and might have been quite useful, if …

Bad iPhone Apps

July 29, 2009 – 4:37 pm | 5 Comments
Bad iPhone Apps

Oh quit your whining, you will say, they are just a couple bucks each, so no big loss if some iPhone apps turn out to be trash. True, but they are so addictive. My first …