Couple days ago I mentioned about calculating the sunrise and sunset times. It is an interesting problem so after reading Astronomy Answers – Position of the Sun I quickly implemented it using C language. It is only an experiment so results are approximate.
How to convert date to Julian Day Number using shell script
I was wondering how to calculate Julian Day Number as I will need it to determine the sunrise and sunset times. Algorithms are extensively described so I will just point you to the two most useful pages –
After a short while I wrote a shell script to convert between Gregorian calendar date and Julian Day Number.
How to display min and max values of the basic object types
Today as a small experiment I wrote very simple C program to display min and max values of the basic object types.
CentOS 6 – _netdev fstab option and netfs service
Yesterday I had a small problem. I have added GlusterFS mount point to the fstab but filesystem wasn’t mounted automatically after I rebooted the operating system (CentOS).
How to open manual page at the specific page section
After writing previous blog entry I started to think about how to specify page section when opening manual page. It is simple but quite interesting issue so I quickly got curious and wrote this post to describe straight solution. Just to be clear – I need to mention that I am not writing about section numbers describing distinct subject areas but just page sections, such as NAME, SYNOPSIS, DESCRIPTION, AUTHORS and so on.
How to change port forwardings during the SSH connection
Last year I wrote a short article about how to set up SSH port forwarding but I forgot to mention that you can quickly terminate existing port forwardings and create new ones during the SSH connection.
How to relay selected mailboxes using ISPConfig 3
I hit an intriguing problem as I needed to relay selected mailboxes rather than the whole domain. I assume that you have already noticed that everything needs to happen on the same domain. It is rare and quite interesting task so I will quickly describe it here using ISPConfig 3 but beware as this is a very specific topic so I strongly suggest to investigate it further before applying any changes.
CentOS 6 – RepoForge and Advanced Policy Firewall
Hmm… Today I hit funny problem as I couldn’t install Advanced Policy Firewall from RepoForge (RPMforge) repository on CentOS 6. Fortunately the solution is trivial and doesn’t require any magic…
Brief note on the MySQL Master-Slave replication
What to do when you want to analyze data contained in database without overloading the server? The answer is simple as you can use MySQL Master-Slave replication to offload this task. I will describe it briefly here.
Ajenti – Clean and simple web-based administration tool
Recently I was searching for clean and simple web-based administration tool for a couple of small virtual servers so I decided to use Ajenti. It is simple and easily extendable administration/monitoring utility using Python language. Installation is very straightforward as there are packages available for FreeBSD operating system and a couple of Linux distributions.