What is the election of Master hosts in the VMware vSphere high availability architecture
This article will explain in detail about the election of Master hosts in the VMware vSphere high-availability architecture. The content of the article is of high quality, so the editor will share it for you as a reference. I hope you will have some understanding of the relevant knowledge after reading this article.
VMware vSphere can deploy one or more ESXi hosts. Because it is a commercial software, its authorization method is generally VMware vSphere Standard Edition, and it can install 2-64 ESXi hosts. There is another authorization model called vSphere Essential Plus Kit, which only supports three ESXi hosts.
Multiple vSphere ESXi hosts work together, and in order to achieve the high availability (High Availibility) function, one is automatically "elected" as Master, and the other is Slave. The election is automatic and usually takes only 15 seconds. There are two conditions for comparison:
1) the number of Datastore mounted to the host, not the capacity, but the number
2) number of objects managed by the host (MOID-Managed Object ID)
The method of MOID comparison is strange. Compare the numbers on the left first. If 98 objects are managed by A host and 100 objects are managed by B host, An is considered to manage more objects than B, that is, 9 to 1. It's not fair that 100 is smaller than 98. However, if one is 98 and the other is 99, then 99 is big and fair. The Master host monitors the "heartbeat" of all member ESXi hosts through management to create conditions for highly available applications.
Under PowerCLI, you can view the MOID of a host from the command line.
PowerCLI C:\ > Get-VMHost | Select Name,ID
Image above: in this SA-Compute-01 cluster, there are two hosts: sa-esxi-01.vclass.local and sa-esxi-02.vclass.local. After "election", sa-esxi-02.vclass.local becomes the Master of the cluster.
So much for the election of Master hosts in the VMware vSphere high-availability architecture. I hope the above content can be of some help and learn more. If you think the article is good, you can share it for more people to see.
