Today one of our cloudservers had some really strange network problems I could not explain. At first I thought it was caused by a mini DDOS or something similair but that wasn’t the case. After spitting through all apache log files and still not being able to fix the problem I found the following kernel messages.
[20328.506805] dst cache overflow
[20328.508511] dst cache overflow
After googling at these messages I found out that the routing cache of the machine was being filled, and that network problems were caused due to this full routing cache.
To fix this problem I decided to increase the routing cache max size, by putting the following in /etc/sysctl.conf
net.ipv4.route.max_size = 2097152
This article describes CRUD operations on MongoDB. Create, Read, Update, Delete (CRUD) are the four basic storage functions for data storage.
MongoDB’s explain command provides information on the query that is being performed by MongoDB.
Indexes are the subject of week 4 of MongoDB University. Don’t worry the weeks between 1 and 4 will come along
Indexes are the single most important factor in database performance. Having no indexes or indexes on the wrong fields can make your application extreme slow. Verder lezen
About a month ago I decided to broaden my horizon by signing in for a study of MongoDB. It turned out that this course was given in Python, another language that was on my wishlist. Currently I’m in week 3 and I felt it was time to make a little summary for the things I’ve learned. Verder lezen
Yesterday I was having trouble entering the recovery mode of Ubuntu. Selecting the recovery mode just resulted into a normal boot even when I added “single” to the kernel boot options in Grub. A friend told me that adding the following phrase to the kernel boot options would help me drop to the root prompt without having the root filesystem mounted.
# Append the following part to the kernel line in GRUB
Having trouble using Vendor code in your CakePHP 2.x application because of namespaces? Hope that this little snippet will help you solving that problem.
New Relic is an application monitoring solution for PHP (and other languages) which gives you more information about the performance of your application. It works well with all major frameworks (including CakePHP). Little problem for me is that CakePHP has it’s own error handling – which catches any error before it can be fetched by the New Relic PHP agent.
Because our server and availability monitoring is already done by New Relic, I decided to build a custom error handler in CakePHP which uses the PHP API of the New Relic PHP Agent. So all monitoring can be done through New Relic.
You can find the plugin with the error handler here: https://github.com/turnred/newrelic-cakephp (Work In Progress)