Prime Time for ESXi
    
		I've been  working with ESXi for a while in both private lab and non-production workloads.  For VI3 installations, ESXi 3 was relegated to toy and science experiment  levels. With vSphere, I'm putting ESXi as the single product going forward in  my virtualization practice. 
Before the  hecklers roll in, let me first clarify a few things about ESXi.
First of  all, ESXi is fully capable of all of the vCenter features that are available to  ESX. This includes vMotion, HA, Fault Tolerance and DRS. These features come  alive when the host is configured to use the licensing allocated from the  vCenter Server. While it's true that the free edition of ESXi doesn't support  the management features, it's just a licensing difference to the same product. 
For new  vSphere implementations, I'm starting out with ESXi in production-class  workloads. Is this going to be a learning curve? Absolutely. But each of these  workloads is fully covered with VMware support. Just as we learned tricks in  ESX to kill orphaned virtual machines, we may have to learn tricks on ESXi.
My  conservative side has arranged avenues of escape, should I change my mind. (We've  never changed our mind in virtualization, now, have we?) In a licensed vSphere  cluster with features like DRS and vMotion, a running virtual machine can be  migrated to an ESX host from an ESXi host. The shared storage driver (VMFS), of  course, is fully compatible between the two platforms. This makes for an easy  host reconfiguration should that course of action be required. Even with the  current sticking point of   an issue that can affect ESXi hosts by not being able to update the host  hypervisor, the simplicity of ESXi is welcome and clearly VMware's direction.
Thus far,  it has been a very smooth transition. Waiting for vSphere Update 1 was likely a  good indicator of readiness (conservative side showing through), as well as  ample lab and test time. Where are you with ESXi? Share your comments below. 
 
	Posted by Rick Vanover on 12/14/2009 at 12:47 PM