There seemed to be a lot of confusion regarding the functiona definiton of a hypervisor so I will elucidate:
Hypervisor: (http://en.wikipedia.org/wiki/Hypervisor )A hypervisors main function is manage different VM's. Hypersvisors is also responsible for the instantiation and termination of a VM. Now there is both a software and hardware based hypervisor. VMware and IBM's DLPAR (Dynamic logical partitioning) technoogy are both of this iteration. The hardware based hypervisor is it's own OS. This allows the system to remain up even if the other VM's crash. IBM"s has had hardware hypervisors ever since the introduction of S/390. DLPAR is highly advance load balancing VM technology on IBM's Power and PPC platforms. DLPAR has the ability start or end new VM's as the systems requirements is changing. VM technoogy is not a new technology at least for IBM Z-Series. IBM"s MVS (Multiple Virtual Systems) refers to multiple VM's running multiple instances of S/390. But beyond all this the S/390 can run simultaneous parallel trancations (IBM parallel sysplex: allows for clustered Z-series boxes) as well with full rollback cability. So in other words a enterprise has not only system fault tolerance, but application fault tolerance as well. So it becomes clearer why so many forturne 500 enterprises still run mainframes. Now I have heard of people scripting VM failover wht VMWare, but I have not had a chance to investigate this more thoroughly. -- ___________________________________________________ Play 100s of games for FREE! http://games.mail.com/ -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
