Is it possible to share a disk between two or more Virtual Machines? Can we use the disk on the two VMs at the same time, for reading and writing?
The answer is Yes and No respectively.
Yes, Nutanix supports shared disk via Volume Group on AHV. This is supported on clustering solutions (Cluster at guest OS level) like My SQL etc.
You can use the disk on the two VMs at the same time for reading. However, two VMs writing at the same time is not allowed.
In a clustering solution, the master VM will write to the disk and all the other VMs in the cluster can read from the disk.
Take a look at the guide to have an overview of how storage management is done at Nutanix:- https://portal.nutanix.com/#/page/docs/details?targetId=Web-Console-Guide-Prism-v5_16:wc-storage-management-wc-c.html