I was facing an issue, On vSAN hosts randomly following error occurs “Host is not in connected state” and at that time vm creation test fails and too much slowness while creating vm manually.
From what you tell me there could be network problems, did you simply try to launch from the vcenter (connected via ssh) a ping to the host that gives you problems?
@aqeel_88 From what to what are you checking ping? Checking this properly is essential e.g. not just Management to Management vmk but vSAN to vSAN vmk also e.g:
# vmkping -I vmk2 -s 8972 -d <otherNodesvSANvmkIP>
What does vSAN Health say? e.g. are all nodes reporting to this and is it Green for all relevant checks under Cluster and Network?
Cluster > Monitor > vSAN > Health/Skyline Health
What does VM creation test say when it fails and what Storage Policy is configured as the vsanDatastore default (as this is the one it will try to use)?
A typical failure message would be 'need 3 Fault Domains, found 1' e.g. indicating only one node is contributing usable storage (e.g. cluster is partitioned, or 2 of the 3 nodes are in Maintenance Mode or only 1 node has Disk-Groups added).