Andrey Mikhalchuk’s Blog

I recently switched to a different computer and got all gems in the system updated approximately at the same time. Not sure what exactly lead to the problem, but debugging the app in NetBeans became impossible because it stopped stopping on breakpoints. To add some confusion, breakpoints were still working in tests, as I discovered later, just not when I was doing something in Firefox. I tried all recipes including

• Upgrading Netbeans to the most recent version supporting RoR (Netbeans sropped Ruby support and the latest version still supporting it is 6.0.1)
• Checking the extended attributes of all folders. Apparently in MacOS if the project folder has an extended attribute NetBeans can’t debug it. Every time you use “extended” HFS+ features like changing background color of a directory in Finder MacOS adds an “extended” attribute to that folder. You can see it but running “ls -l” and noticing “@” character in the file permissions.
• checking if rdebug is running fine. I used telnet and wireshark to see the communications between rdebug and NetBeans and saw all breakpoints set properly.

So nothing helped until …

I tried to figure out how rails reacts to the fact that memcached goes down. Unfortunately there is no god documentation about this besides saying that everything will be fine. Also there are couple misleading posts in different forums saying that rails will never rediscover memcached server that went down and came back again. Here’s what is actually happening…

I was recently compiling some Arduino code with NewSoftSerial and got hit by infamous “Error: register r24, r26, r28 or r30 required” error. NewSoftSerial is a great library and those using older avr-gcc compiler enjoy it alot. Problem is the newer gcc doesn’t like one nasty error in the code and here is how to fix it …

Many people are dreaming about consolidating all media files (video, music, pictures etc) in a single place. For some it is a huge full of DVDs, CDs and photos. Others buy hardware media servers and store all files in them. I chose a solution based on Archos 605 WiFi and a Linux Server running UPnP Media Server. Here’s how it works …

Last 12 months I was working on an interesting device that provides the network security features many companies and families are dreaming about. You probably already have heard about different threats out there like internet predators, viruses, spyware, dangerous websites, confidential information leaking from your business and others. Also you probably tried to find answers to questions like

• Is my office network used appropriately? Do people really use it for work and not something else?
• Are my kids safe in the Internet? Are their virtual friends really friends?
• Why is my internet so slow?
• Who in my network is using the internet most, when and what for?
• How can I prevent my children or employees from browsing inappropriate content, wasting time in chats or games?

Finally, you might want to get answers to the questions immediately and you don’t want to spend a lot of time configuring every single computer in your network, installing software and other techi stuff … So the answer to all those questions is one small box called MineStream Defender and here is what it can do …

You ran ./configure and got “configure: error: C++ compiler cannot create executables”. Here is how to fix it …

I was recently installing squid at home as a single caching proxy for all computers in my home network. The simple way is just running squid on your linux router as is and configuring every single browser on all computers in your network so they access internet using squid. That’s doable, but boring. The more interesting way is setting up transparent proxy so all your http traffic goes through squid automatically. I’m not going to explain how to setup the transparent proxy as there are tons of articles in the internet about that, for instance:

• http://www.cyberciti.biz/tips/linux-setup-transparent-proxy-squid-howto.html
• http://tldp.org/HOWTO/TransparentProxy.html
• http://www.deckle.co.za/squid-users-guide/Transparent_Caching/Proxy

The documentation is very straightforward, and has just one problem: it is outdated and doesn’t work with the most recent versions of squid. I’ve read several instructions and was always ending up with these error messages:

Here’s how to fix the problem …

I prepared a page with my favorite software review. Most (if not all) of the utilities are for free and I hope you will enjoy those useful tools.

Imagine you need to create say 10 disks with predefined partitions loaded with some software. The ideal solution would be automatic disk partitioning and copying the software to it. While copying files is an easy-to-do everyday procedure partitioning is a bit more tricky (really, just a little bit). Here is a quick trick that will allow you to partition disks quickly.

Uff that was tough one … If you decided to make your mail communications more secure you probably switched on SSL option in your mail client for POP3/IMAP/SMTP servers. There is a good chance you will get one of those errors that sound like

The server you are connected to is using a security certificare that could not be verified.
A certificate chain processed, but terminated in a root certificate which is not trusted by the trust provider.
Do you want to continue using this server?

I spent way too much time solving the problem because what was just annoying message in Outlook appeared to be serious problem in MacMail. It was not capable of working correctly with that problem. In addition to that I tried to solve the problem using Plesk 8.2 that was a mistake. It appeared that whatever you do with certificates in Plesk that doesn’t affect the mail. So here is the solution for the problem: