Do you need VMware ESX? (vSphere)

Update:1 – corrected some numbers. Thanks @jasonboche

Let me just say I love VMware, particularly ESX and have worked with it from before GSX was in shorts, back in the workstation days, when only para-virtualisation existed. I have rolled out ESX 2/3/4 farms (no 5 yet)… I have never had a purple screen of death, I have never had to rollback a workload to hardware, I have VMed Exchange 2k/2k3/2k7, DCs 2k-2k8r2, file & print, SQL servers, Citrix servers they all run great on ESX/ESXi.

But do you need it? Or are you after a solution has all the features, are you after the Rolls Royce? What are you really trying to do? Are you exotic or somehow special?

You want ESXi that's fine, go ahead I don't get paid either way, but then nor does anyone so please do.

Lets just think about what server virtualisation does (as of todays date):

Feature	ESX/ESXi	Hyper-V	XENserver
Bare-metal architecture	Yes	No, but core	Yes
VMotion like	Yes	Yes	Yes
Small footprint	Yes	No, but core	Yes-ish
Cluster (pool)	32 nodes	16 nodes	16 nodes
CPU virtualisation	Yes	Yes	Yes
RAM Support Host	2TB	1TB	1TB
RAM support VM	1TB	64GB	128GB
RAM overcommit	Yes	Yes	Yes
NIC teaming	Yes	No*/vendors	Yes
VM RAM Page sharing	Yes	No	No
Ballooning	Yes	Yes	Yes
Capacity prioritisation	Yes	Yes-ish	Yes-ish
Traffic Shaping	Yes	No	No
Virtual NIC	Yes	Yes	Yes
Virtual switches	Yes	Yes	Yes
VLAN tagging	Yes	Yes	Yes
Dynamic volume resizing	Yes	Yes	Yes
Raw device mapping	Yes	Yes	Yes
LUN management	Yes	Yes-via vendors	Yes-add on
Guest Windows	Yes	Yes	Yes
Guest Linux	Yes	Yes-limited	Yes-good
Guest Other	Great	OK	Good
Paravirtualisation	None (good!)	Yes, LAN/Disk	yes-ish
Distributed Power Mgnt	Yes	Some	Some
Wake-on LAN	Yes	No	No

There are hundreds more features such as “Boot from SAN” which are specific or particular so I have not listed them above, if YOU need them they are critical but lets just focus back on the 99%

So to look at this list above there are some clear areas where ESXi wins out, specifically on the very large scale, telco scale, intensive power saving, dare I say cloud providers… But if you are one of the people who just need a bunch of VMs per server for general workloads any of the three products above is going to work fine. Scale up the CPU, RAM, Network cards and you can go to higher density?

The limits are disappearing.

So now lets look back at yourself, do you really need ESX? Maybe you could save some money… Look around.

Just before signing off, read this: http://www.thincomputing.net/2011/03/07/how-many-users-can-i-host-per-server-with-remotefx-for-hyper-v-and-what-is-the-cost-per-user/

This document is the source for the core of this post:
“vmware-vsphere-features-comparison-ch-en.pdf”
Intel: “xeon_7500_Virtualization_solbrief.pdf”

* Microsoft say dont use teaming, but vendors support it. Buyer beware… Microsoft Support Policy for NIC Teaming with Hyper-V - http://support.microsoft.com/kb/968703