With a vsan issue where you cant access vcenter, should you ssh into all machines and power them down prior to restarting esxi host?

Solution 1:

Please clarify, is it StarWind vSAN https://www.starwindsoftware.com/starwind-virtual-san or VMware vSAN https://www.vmware.com/products/vsan.html as these two share the same name, but are two very different products under the hood.

For my perspective, I had no issues with StarWind running SDS for VMware vSphere. Can't say much about VMware's. In your case, I would shut down all VMs manually via SSH and then reboot the VMware vCenter. But firstly, I would check backups and might try to run a backup job to have recent ones.

Also, you could try to reboot just vCenter VM. https://kb.vmware.com/s/article/1004340