Although Kamailio supports basic arithmetic, it does so only using configuration variables and not dynamic variables. Due to its flexibility, it is just a matter of time until you will come up with an idea where you would need to use dynamic variables for some form of arithmetic calculations. In version 5.7.0 released on May 17th 2023, a Math module was released with 5 functions, mainly around logarithmic and square root computation.

Some time back as a quick Golang project I built my own ‘what is my IP’ web service. Aside from learning a bit of Golang, I did not have any real use case for it. However, recently when a friend and I were working on some AWS EC2 instances in China, we quickly needed to know our public IP so my friend did what everyone would do curl ifconfig.me To our surprise the connection timed out 😲.

Sometimes your Kamailio server might need server maintenance and for that you could require a way to drain out traffic. Also, depending on where it sits in your design you might want to return a custom response code so that new traffic routes elsewhere. There is a simple trick to doing this. The idea is simple, set a variable and check its status/value and based on that decide on how to handle new requests.

After every manual installation of Kamailio from git, it is best practice to create an init.d or systemd script to easily start, stop or restart the Kamailio service. A lot of people are still in the habit of creating these scripts manually because it probably was a step they added in their installation scripts years back. Yes, we are all creatures of habit but for a while now there is reason for a change in this habit.

Have you been caught in the situation where a project you thought would be simple and low maintenance turned out to be popular and now you are faced with the problem of logging into servers and doing repeated tasks because you haven’t had enough ‘free’ time to automate some of your processes? A quick bandaid could be pssh (Parallel SSH). PSSH Quick Intro Pssh lets you log into multiple servers at the same time and run commands.

When we need to mangle or massage some data on a Linux/UNIX server or desktop, we usually like to use applications like Google Sheets or other fully fledged data processing software forgetting about pipes. A basic description of the pipe ( | ) is that it allows the output of one command to be the input of another. What this lets you do is filter data in steps as you chain commands.