vSAN availability

In this section, we will discuss high availability in a VxRail vSAN cluster. This includes the vSAN fault domains and maintenance mode. Now we will discuss these aspects.

Overview of vSAN fault domains

vSAN fault domains are used to ensure protection against rack or room failure, and we can create fault domains for vSAN high availability. A fault domain consists of a vSAN host or more vSAN hosts in a physical location, for example, racks or data centers. When we define fault domains, it depends on the vSAN tolerate failures of entire physical racks, a single host, disk devices, the network switch, and so on.

Now we will discuss an example. Figure 5.28 shows an example of fault domains in a VxRail vSAN cluster:

Figure 5.28 – vSAN fault domain example

The minimum requirement for fault domains is three domains. In best practice, four or more fault domains is the recommended configuration. In Figure 5.28, there are eight nodes...