Virtual machine based operating system simulation using host ram-based emulation of persistent mass storage device

A method comprising:

• executing a guest operating system as a virtual machine on a first physical host, the guest operating system including a network storage operating system, the virtual machine operating as a virtual storage server or a simulated storage server, the first physical host including a plurality of host slots, each of the host slots capable of executing a different virtual machine, the first physical host including random access memory (RAM);
• using at least a portion of the RAM as a RAM drive to emulate a virtual, secondary, persistent mass storage device of the virtual machine controlled by the guest operating system, wherein using said at least a portion of the RAM as a RAM drive includes
• creating a mount point for a host slot of the host slots that is executing the virtual machine, and
• mounting the RAM drive on the created mount point;
• using the RAM drive to store a data image file of the virtual machine, wherein the data image file represents the virtual, secondary, persistent mass storage device of the virtual storage server;
• detecting a request to move the virtual machine from the first physical host to a second physical host;
• and
• in response to the request to move the virtual machine from the first physical host to a second physical host,
• unbinding the virtual machine from the first physical host;
• causing contents of the RAM drive to be sent over a network to a server and stored persistently in the server as one or more datasets, the server coupled to communicate with the second physical host;
• binding the virtual machine to the second physical host;
• and
• sending said one or more datasets from the server to the second physical host and storing the one or more datasets in at least a portion of RAM of the second physical host, said at least a portion of RAM of the second physical host being used as a RAM drive controlled by the virtual machine on the second physical host.

A system comprising:

• a server;
• and
• a first physical host coupled to the server via a network, the first physical host including
• a plurality of host slots, each of the host slots capable of executing a different virtual machine,
• a host random access memory (RAM),
• a guest operating system operable as a virtual machine on the first physical host, the guest operating system including a network storage operating system, the virtual machine operating as a virtual storage server or a simulated storage server, wherein in operation the guest operating system uses at least a portion of the host RAM as a RAM drive to emulate a virtual, secondary, persistent mass storage device of the virtual machine controlled by the guest operating system, wherein using said at least a portion of the host RAM as a RAM drive includes
• creating a mount point for a host slot of the host slots that is executing the virtual machine, and
• mounting the RAM drive on the created mount point, and
• wherein the quest operating system further uses the RAM drive to store a data image file of the virtual machine, the data image file representing the virtual, secondary, persistent mass storage device of the virtual storage server, and
• a host operating system configured to respond to an event associated with an interruption in operation of the virtual machine, by causing contents of the RAM drive to be sent over the network to the server and stored persistently in the server.