IT | Arik Yavilevich's blog

Real-time location tracking of individuals or things that are important to you

Dec

19

2020

When I was taking my young kids to the park or playground I wished I had a solution that would tell me where they are in case they go out of sight. This led me to a project where I made a system to tell me in which direction (AKA bearing) and how far a ...

Capturing and reversing wireless keyboard signal

Sep

4

2016

Recently I have made a presentation at the “Software Defined Radio Israel” meetup about my work capturing and reversing wireless keyboard signals. I focused on a “Rapoo E2700 keyboard and track-pad” but we also discussed the broader challenge of such capturing for SDR enthusiasts. The project involved capturing 2.4Ghz wireless signal with an RTL-SDR dongle ...

Experiments with dead space reclamation and the wonders of storage over-provisioning 3

Jan

24

2016

I am in the process of setting up a home storage server that will rely heavily on over-provisioning. You can read more about my previous VMware – FreeNAS – ZFS experiences in other articles. In this article I will conduct several experiments showing how available disk space fluctuates at various layers in the system. This ...

Why use – SoundWire? 11

Dec

18

2015

SoundWire is a nifty little app that lets you listen to sound that normally comes out of your Windows (or Linux) PC on an Android device. The main use of this for me is as “wireless headphones” for listening to YouTube or movies that the PC can play without really purchasing actual wireless headphones. The ...

DiskSpdAuto: Automating IO performance tests and result collection using DiskSpd and PowerShell 3

Oct

25

2015

If you have followed my previous article titled IO Performance Benchmarking 101, you know that I am a big fan of using CrystalDiskMark for measuring disk IO throughput. CrystalDiskMark is a wonderful tool, but being a GUI application it is unsuitable for using in an automated environment or when you need to test several disks ...

Quirks of ZFS interoperability 3

Oct

2

2015

My main tech project in the last few month has been an all-in-one home lab. The lab is a high-end PC running a hypervisor, which hosts VMs and provides a flexible infrastructure for experiments. One of the main components of such a setup is a storage VM that provides storage to other VMs, while giving ...

IO performance benchmark of unsupported ESXi configurations 2

May

28

2015

Introduction VMware is a serious platform for enterprise-scale virtualization. VMware also offers a free ESXi hypervisor and plenty of individuals choose to use that for various small setups, such as home labs or home infrastructure. VMware maintains a list of hardware devices, which are compatible with the hypervisor. VMware products also implement many features and ...

Dissecting a broken hard disk drive

Apr

2

2015

A year ago I had an unfortunate accident, in which I dropped a barely used 2TB WD Green drive. It fell from about 30cm height onto a hard surface, creating a noticeable dent on the outside. It stopped working on the spot, making unusual sounds and cycling down instead of operating normally. On the one ...

Dear Gigya CEO, JavaScript files are important

Dec

2

2014

A few days ago, news broke about a large-scale hack of various sites by the Syrian Electronic Army. The motivation behind the hack was political and the only damage came down to a popup message: “You’ve been hacked by the Syrian Electronic Army (SEA).”. Happy thanks giving, hope you didn't miss us! The press: Please ...

Restarting while expanding a RAID can get your server to get stuck at boot 3

Oct

27

2014

The ability to do an online RAID capacity expansion is something we had for some time. Still, every time I do this I feel like I am doing something amazing and state-of-the-art. The idea that you can expand an existing volume without losing any data and without downtime is almost magical and requires some clever ...