vSAN Health Service - Cluster Health - vSAN Direct Homogeneous Disk Claiming

Products

• VMware vSAN

Issue/Introduction

This article explains the Cluster Health - vSAN Direct homogeneous disk claiming check in the vSAN health service and provides details about why it might report an error.

Environment

VMware vSAN 7.0 U2 and higher 

Resolution

Q: What does the Cluster Health - vSAN Direct homogeneous disk claiming check do?

It will check if there is homogeneous configuration of vSAN direct storage claimed on each host in the cluster, including the number of vSAN direct disks, the physical disk type (SSD or HDD) and the capacity of each vSAN direct disk. And show as "yellow" when it is not.

Q: What does it mean if it shows a warning state?

It means that vSAN Direct disks claiming are not homogeneously among hosts in the cluster. Then there might be failures in creating Persistent Volumes and hence failures in bringing up stateful Pods in the Supervisor Cluster.

Examples of warning state:
In a cluster with 2 hosts, if one host claimed 3 vSAN Direct datastores while the other one claimed 2 vSAN Direct datastores.
In a cluster with 2 hosts, both hosts have claimed 1 vSAN Direct datastore. One host claimed vSAN Direct datastore with disk type A and capacity B while another claimed vSAN Direct datastore with disk type C and capacity B.
In a cluster with 2 hosts, both hosts have claimed 1 vSAN Direct datastore. One host claimed vSAN Direct datastore with disk type A and capacity B while another claimed vSAN Direct datastore with disk type A and capacity D.

Q: How does one troubleshoot and fix the warning state?

Firstly, check the "vSAN Direct homogeneous disk claiming" page. It will give you a summary of all vSAN Direct storages that have been claimed on each host in the cluster. You can fix the difference to meet the requirements.