What’s Split Brain and how to avoid it like the plague?
Posted by Sergey Sanduliak on January 3, 2018
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In this article, we will discuss the split brain issue, and different approaches to prevent it from happening.

The situation when communication loss between the cluster nodes is caused by network connection problems is called network partition, which can lead to split brain. According to Wikipedia, split brain is a computer term, based on an analogy with the medical split-brain syndrome. It can be a real horror for a system administrator to handle the consequences of a split brain.

A split brain can happen if active nodes lose all synchronization and heartbeat connections between them at the same time and are not able to communicate anymore to define the synchronization state of the partner node. Split brain indicates data or availability inconsistencies originating from the maintenance of two separate data sets with overlap in scope.

split brain syndrome

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vCenter Server High Availability Review – Part 1
Posted by Askar Kopbayev on November 24, 2016
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VCHA overview

High Availability for vCenter Server has never been as important as today when there are so many products dependant on vCenter, e.g. VMware NSX, vSAN, Horizon View, etc.

VMware tried different approaches to bring HA to the vCenter.

There has been vSphere HA for a long time. Although it can protect vCenter Server from hardware failure it doesn’t provide protection on the Guest OS level. So, if Postgres DB in vCenter Server Appliance gets corrupted you would have to restore vCSA from a backup copy or rebuild it from the scratch.

standard topology of VCHA

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