Following the a customer suggestion, I've looked at www.marathon.com a company which provides high-reliability software solutions.
Here my personal annotations:
Marathon everRun VM
Provides extensions to give high-reliability to Citrix XenServer.
Good to know but usually we work deploying VMWare which has other ways to provide reliable configurations.
Marathon everRun HT & FT
everRun is a virtual environment which creates a virtual logical server leveraging 2 physical servers. We can think to it as a cluster without using Microsoft cluster service and should be easier to maintain.
The synchronization at disk level is provided duplicating all the writes operations on both physical disks over the 2 physical servers. The write is transacted and an Ack is sent back to the physical servers only when the operation has been completed on both systems.
My concern are just for the performances but at a basic level no dedicated hardware is required to provide high-reliability.
We are internally evaluating the platform to provide real high-reliability to SCADAti\
Provides geographic redundancy but I don't understand which kind and how...
I think that in some way it leverages the distributed transactional writing having high-reliability over a files system (excluding application executions).
Like for SplitSite I haven't understand so well the product scope. It should enlarge the functionalities of everRun HT & FT providing them geographic redundancy. It should work as a kind of synchronizer for all the everRun servers.