Welcome to the forum.
Can you access your datastores and browse VM files from VI Client? If your devices and servers restarted automatically, maybe you can stop them properly and restart them in the right order, disk devices first...
Hope it helps. Good luck.
1. What type of storage are you using for your VM's (FC/ISCSI)?
2. Are you able to browse the data store and see any files in it?
3. Can you login to the service console and check if the VM files are there under /vmfs/volumes/?