Merge pull request #75513 from lpettyjo/OSDOCS-9516

OSDOCS-9516# vSphere compliance requirements

Author: lpettyjo

modules/persistent-storage-csi-vsphere-top-aware-overview.adoc

@@ -26,4 +26,20 @@ Datacenter: Atlanta
 Datacenter: Atlanta
 |openshift-region: us-east-1 (tag), openshift-zone: us-east-1b (tag)
 |This defines a different failure domain within the same region called us-east-1b.
-|===
+|===
+
+== vSphere CSI topology requirements 
+The following guidelines are recommended for vSphere CSI topology:
+
+* You are strongly recommended to add topology tags to datacenters and compute clusters, and *not* to hosts. 
++
+`vsphere-problem-detector` provides alerts if the `openshift-region` or `openshift-zone` tags are not defined at the datacenter or compute cluster level, and each topology tag (`openshift-region` or `openshift-zone`) should occur only once in the hierarchy.
++
+[NOTE]
+====
+Ignoring this recommendation only results in a log warning from the CSI driver and duplicate tags lower in the hierarchy, such as hosts, are ignored; VMware considers this an invalid configuration, and therefore to prevent problems you should not use it.
+====
+
+* Volume provisioning requests in topology-aware environments attempt to create volumes in datastores accessible to all hosts under a given topology segment. This includes hosts that do not have Kubernetes node VMs running on them. For example, if the vSphere Container Storage Plug-in driver receives a request to provision a volume in zone-a, applied on the Datacenter dc-1, all hosts under dc-1 must have access to the datastore selected for volume provisioning. The hosts include those that are directly under dc-1, and those that are a part of clusters inside dc-1.
+
+* For additional recommendations, you should read the VMware https://docs.vmware.com/en/VMware-vSphere-Container-Storage-Plug-in/3.0/vmware-vsphere-csp-getting-started/GUID-162E7582-723B-4A0F-A937-3ACE82EAFD31.html[Guidelines and Best Practices for Deployment with Topology] section.