Using MongoDB as a queue

For some reason, I was very curious about NoSQL technologies when they started gaining hype against traditional RDBMS systems.

Maybe because I was a firm believer that for certain tasks RDBMS systems just excel. And of course I am talking about tasks that ACID properties are crucial. Or about tasks that transactions are much needed.

But all those fanatics trying to prove that MongoDB is a high performance “web scale” database got me curious.

So I started playing with it.

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Rackspace’s DNS rate limiting

Today, while I was having lunch, I started receiving email notifications about Niume’s servers not responding. In the beginning it was just one server, so I removed it from the load balancer, then restarted the httpd process and put it back again.

But then the other servers started behaving the same way, even though the load was well under capacity. Between those email notifications, there was a Rackspace support email:

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Motion Detection Surveillance System with raspberry pi

One of these days, the disc brake lock of my bike couldn’t unlock. My first thought was that somebody tried to steal the bike. Probably this isn’t the case, but I took some immediate measures to restore my inner peace again.

I used to have a windows laptop running yawcam (Yet Another Webcam Software) and recording images when motion was detected. But this laptop is now dead and I don’t use Windows at all anymore, so I had to find a Linux equivalent.

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Media Discovery Black Hat SEO scam

So, I received an email the other day from a company called Media Discovery, offering me monies in order to sell them advertising space for this very blog.

To make a long story short, it wasn’t a completely spam email, just spam-ish. The first email I received in January the 21th was the following one:

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Install sendEmail (simple SMTP client for Linux) on CentOS

I have a lot of servers up and running doing various tasks. They run scripts, and for most of the scripts I want to know if the outcome was good or bad. Especially bad.

The most common and easy way is to send an email for most of the cases, but I don’t want to setup a mailserver such as postfix in order to do it. I prefer to just use a gmail address in order to complete the task easily.

I found an application-utility which does exactly this simple thing. It is written in perl and it is called sendEmail – not to be confused with sendmail. I figured out that because I just install it when I set up a new server, I can’t find any complete instructions and I need to search around every time in order to make it work. Note that you cannot find sendEmail in the usual yum repositories.

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Recruitment Ranting

As the Chief Software Engineer of Niume Ltd and as a person who thinks that the Recruitment Industry does not perform well within the Software Industry (apart from gathering CVs), I have to personally interview and test the skills of each applicant.

Because of this, I stumble upon millions of things that annoy me and can be pretty well summarized in this blog post here and this one here, written by a fellow software developer in Greece. Since Greek is not the language the masses are familiar with, I am going to translate most of the points made and maybe add mine too, in order to make applicants more successful next time.

So, let the ranting begin.

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Setup CentOS 6.4 to run PHP 5.5

I always use the PHP mysql native driver aka mysqlnd when I develop something serious in PHP. Because of many reasons, both of performance and software design nature.

I’ve learned the hard way that the trio mysqlnd – CentOS 6 – PHP 5.3 is never a happy story, unless you have a system administrator sitting around to compile PHP 5.3 with the mysqlnd option in configure command every time you setup another web server. I don’t want to go further to other implications, to be honest I hate being logged in as root and I try to make my visits as short as possible. Sometimes I wonder how sysadmins can like their job.

So, I took a leap of faith, I upgraded all my servers to CentOS 6.4 and I installed PHP 5.5 which ships with mysqlnd and did all the management with yum. Sweet.

It is a bit trickier than it seems though. The default PHP that ships with CentOS 6.4 is PHP 5.3.

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Last Push of the Day/Night

All DevOps out there who use Git as a version control system probably know what it feels like. And it is a very special feeling.
(You also get this feeling with SVN by committing but for me it’s not the same.)

I prefer the push thing. I like the semantics, the poetry about it, its cruelty, everything. And I hate it so much at the same time.

The action of pushing is like signing and assuring that the spaceship can launch tomorrow.

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Microfeed

I’ll get straight into the point.

Twitter for me is /dev/null. (a black hole). Also, it lacks the feature of searching my own tweets using different parameters.

Facebook UI on the other side is a moving target. And all of a sudden, my wall posts are being archived every once in a while and do not appear normally. Not to mention the fact that one cannot actually search beneath your posts (and please don’t tell me about graph search) and you don’t own any of your data.

So, I went on and created microfeed.

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PHP 5.3 mysqlnd driver – phpmyadmin problems on Ubuntu Linux Server 12.04

Yesterday, I wanted to install the php-mysqlnd driver on an Ubuntu Linux Server running PHP 5.3. I needed to do that in order to be able to run code like that (it fails miserably otherwise and for me that function is like a swiss knife):

$result = $stmt->get_results();

The procedure was quite straightforward, but it kind of “sacked” phpmyadmin. And when I tried to reinstall it, it was uninstalling the mysqlnd driver.

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