http://searchservervirtualization.techtarget.com , and author Scott Lowe Posted a Blog post titled : Internal vs. external guest virtual machine storage Full Blog Post Here : http://searchservervirtualization.techtarget.com/tip/0,289483,sid94_gci1342097,00.html
Numerous articles have been written about various storage protocols that can be used with VMware to store the files that make up a virtual machine (VM). Little, however, has been published about storage within the VM, such as what the best options are for providing storage to guest VMs and which option is best in a given situation. It is almost guaranteed that the operating system (OS) instance for a particular guest VM will be found within a Virtual Machine Disk Format (VMDK) stored on a supported data store, but that’s not necessarily the case for the data managed by that guest VM. Users have options in how that data will be stored and accessed by the guest VM. In this tip, I’d like to explore some of the options for providing additional storage to guest VMs and when these options are most applicable.
There are essentially two options for providing storage to guest VMs. Users can either provide internal storage by provisioning additional VMDKs at the VMware ESX layer and attach them to the guest VMs, or users can provide external storage by configuring guest VMs to use software iSCSI and attach to an iSCSI-based array.
Each of these options has its own advantages and disadvantages. The reasons for using one approach versus the other lie within these advantages and disadvantages. First, let’s explore these options in a bit more detail.
Full Blog Post Here : http://searchservervirtualization.techtarget.com/tip/0,289483,sid94_gci1342097,00.html
A good read, Thanks Scott.