Awk & sed Snippets for SysAdmins

Clone Raspberry Pi SD to Larger Card

This is more of a note to myself: every time I need to clone the RPi card, I end up googling things for an hour. The process is two-fold: clone the SD and resize the …

Backup Options for Raspberry Pi

Just about every Raspberry Pi I used suffered the same fate: the micro SD card died. It is generally accepted that the expected lifespan of an SD card is around ten years of normal use.

Affordable Linux Server

A friend asked me what server I would recommend to run Linux. Yes, a very broad query. After a few followup questions we’ve determined the server will be used to run VMs, or Apache, or …

Taking Linux Temperature

Just some notes on setting up temperature monitoring and alerting on CentOS/RHEL running on HP ProLiant. The first step is to install lm_sensors:

Oracle Sun SPARC Server Quick Configuration

In the following example we’re using a SPARC T4-2. These systems ship from the manufacturer with pre-installed Solaris 11. After the system has been racked and connected to primary and ILO networks, the first step is to …

Hold Off on iOS 9 iPhone Upgrade

If you haven’t updated your iPhone 6/6 Plus to the recently-released iOS 9, I’d suggest you hold off for a few weeks. Several bugs – including a significant security hole – have surfaced that will …

Tuesday Night Rant: LED Light Bulbs

An off-topic for sure, but after a brief conversation about LED bulbs with a friend – a Contract Electrical – I found I had more arguments then I was willing to spill on Facebook. I …

Raspberry Pi 2 OpenELEC Player

Just some quick documentation, mostly for myself, but feel free to try. This is a Raspberry Pi 2 with OpenELEC. The design is intended for overclocking, good wireless performance, and convenience of dual remotes. This …

Resetting HP ILO from OS

You can use ipmitool package in Linux to reset your HP server’s ILO password. The basic instructions are below.

What To Do When Windows Ignores SD Card

Here’s a common scenario: you insert or swap and SD card in your laptop and… nothing happens. Sometimes Windows decides to ignore the SD card for reasons unknown (well, the true reason is it’s Windows). …

iPhone Stopped Syncing with Google Calendar

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 …

Jailbreaking My iPhone 4S

An iPhone 4S is a fairly sophisticated computer capable of doing many interesting things. Unfortunately, since most phone users are computer idiots, to preserve its bottom line and the sanity of its tech support staff, Apple imposes severe limitations on what you, as a user, can do with your iPhone or iPad. As a Unix sysadmin I am entirely on Apple’s side on this one. However, it would have been nice if Apple allowed an option of full access in exchange for voluntarily voiding the warranty. For those of us who know what they are doing and are not gonna run in tears to the nearest Genius Bar if something goes wrong…

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

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

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

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

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

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

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

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

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

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.