Single machine virtualisation

[theS70RM]

(or virtualization if you aint from round here)

Hey,

Just looking for some advice really. I can see a big advantage of virtualising servers. But suppose I have a server that needs basically all the resources of the machine, what would be any disadvantages of virtualising just the one server onto the machine its on already. Im thinking particularly so the hard disk can be easily backed up and restored somewhere else should the machine develop a fault. Also, what are other advantages other than the one already mentioned.

If you have a virtual machine and give it all the memory etc of the physical machine is there likely to be any great loss in efficiency compared to if it had the same resources but wasnt virtualised? Ok so not the full memory/resources as the machine will need some itself to run the virtual server software etc What would be a balance to get it to run best, split the memory down the middle? give the physical server the bare minimum and the virtual machine the rest? or the other way round?


Any help is appreciated!!

Thanks

Andy

[jg007]

I believe that Virtualisation is mostly used so that you can have several servers with different functions running on one machine so that they are independant of each other and if needed you can take one VM down or make ammendments without affecting the other.

Also if you start using MS VM managment tools you can get very powerfull fail over protection so that if one machine goes it just switches to another with virtually no downtime

I am not sure I could see any benefit with having only one VM on a machine but I could be wrong but I also wouldn't image there would be that much impact on performance if you do decide to virtualise it.unless it was very heavily utilised

there is some extra reading ( MS based ) here -

http://www.microsoft.com/virtualization/promise.mspx