Day 55: Back-up master controller

From the previous posts we can see that we have achieved a huge amount of the architecture we had set out to build!

There was one scenario in the last article, which we have not attended to yet. That is - What if the master controller (which connects to all switches at some point or the other) faces a single point of failure?

This is completely probable as master controller is connected to all switches and installs flows in all of them, even the ones that cause DoS attack on the controllers. Thus, we need to protect the master controller from single point of failure. We shall use the same approach as used in Day 45 to protect load balancer from single point of failure. Thus, we are going to need an additional computer in our network architecture that can act as a back-up master controller.

We are going to use the keepalived tool for the same. My Github page has the code. You could refer to Day 45's code and experiment yourself regarding what changes to be made to the code to implement it as a back-up for master controller rather than a load balancer.

Refer to previous and next posts here.

Author: Shravanya
Co-author: Swati

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