VMFS file system is cluster aware, it handles locking of vmdk files not the actual esx nodes in the cluster.

it's not aware of other hosts but it handles file locking internally,  other ESX hosts would not be able to start the VM if it's already running on other host.  I have two stand-alone ESXi servers (the free version) and both are connected to one LUN from VNX, each server is running a couple of VMs from the same LUN.

So, if you have two ESXX hosts not in a cluster configuration and both of these hosts (in different Storage Groups) share the same LUNs, that the file system will be aware of the other host?

glen

What I'm looking for is documentation that supports either argument.  Either

a) presenting a LUN to several hosts that are not clustered together is perfectly fine, supported, and normal or

b) it should work fine, but it is not best practice, not recommended, and not supported by VMware.

Thanks!

i don't think i have seen anything official. Do they  need to this configuration for some kind of migration ?

VMFS is a cluster file system designed to support up to 32 hosts with simultaneous access..  Each host issues locks to the files they are operating on individually and the other hosts see/respect those locks through their own view of the filesystem.

VMWare clusters are not based on the filesystem and are actually only created to put boundaries on VMWare HA and VMWare DRS and other VM availability features.  There is no requirement to have a host cluster when sharing VMFS volumes, as long as the limitations of VMFS are respected (maximum number of hosts, etc)