
Highlight the host you are getting error on.

Select the Configure tab, System / Security Profile Services click on Edit:

Enable SSH on each host in the VSAN cluster:

Launch a terminal application like Putty to SSH onto your hosts.
Note: When restarting the vCenter Management Agents on the ESXi host, you will get a brief interruption to the host manageability. This is perfectly safe and will resolve itself automatically. In some cases, the host may momentarily enter a not responding state in vCenter Server, however this is rare.
Run the following command to restart the Management Agents:
/etc/init.d/vpxa restart

Run this command on all VSAN nodes. This updates the cluster information in vCenter Server and clears the message.
If you are still getting this error you can try the following:
Remove the host from the VSAN cluster and re-add. This forces all hosts to update the information about the cluster membership and clears the message.
Warning: When you attempt to remove and re-add the host, data synchronisation does not occur when the host is in maintenance mode and out of the VSAN cluster. If you select the Ensure accessibility maintenance mode option, some objects may be unprotected while executing the workaround.
To remove a host from the VSAN cluster and re-add:
- Select the ESXi host in the vSAN cluster that can be put to the maintenance mode temporarily
Best Practice: VMware recommends to select the least busy/utilized host. - In the vSphere Web Client, right-click the ESXi host and click Enter Maintenance Mode.
Note: Select either the Ensure Accessibility or Full data migration options for vSAN maintenance mode. - If applicable, allow powered-off virtual machines to be migrated to the remaining ESXi hosts.
- Remove the host from the vSAN cluster
- Select the host.
- Drag the host out of the cluster.
- Place the host in the datacenter object in the vCenter Server inventory.
- Note: After moving the host into the datacenter, wait for approximately two minutes
- Drag the host back into the vSAN cluster.
- After adding the host back in the vSAN cluster, right-click the host and click Exit Maintenance Mode.
- Note: The message on the remaining hosts should be clear.
Add the ESXi Host back into the VSAN cluster
