I am doing a lot of research into virtualisation and SAN's at the moment and hope to implement a solution once i ahve enough solid information to go on. At the moment I am confused as to the whole idea with LUN's and Virtual machines. I understand a LUN is essentially a partition of an array which is presented for clients to connect to.
It would seem to me that the best way to set luns up is one LUN per VM, for performance reasons, but from what I have read online it would seem this is not the case. Could somebody explain to me how this all works from a VM per LUN perspective? I also understand that in Hyper-V that have introduced cluster shared volumes in order to deal with multiple VM's per LUN so its obviously viable to put more than one VM each.
Could somebody explain this to me, and additionally explain how iSCSI targets are generated/what they are.
I feel like I almost have the idea and just need a correct explanation for things to 'click'.