Citrix released their virtualization solution named XenServer (from version 5, article XenServer is free) for free but only the time will show if it was a right decision. At first glance, it seems like a marvelous thing but there are some facts which should be investigated first. Together with XenServer, it was released central management solution XenCenter.
Let's have a look at their rival VMware (vSphere 4). XenServer is fully comparable to VMware ESX or ESXi. But what about XenCenter management? It's something more than VMware vSphere client but not so valuable as VMware vCenter Management Server. Citrix XenCenter is not the right choice in case of comparison to vCenter. The right one is Citrix Essentials but this one is not for free already. The main differences between Citrix XenCenter and Essentials are:
* XenCenter is missing alerting capabilities like send me an email when "CPU usage is too high" or when some error condition like "virtual machine power on failure" appears
* XenCenter is missing high availability support
* XenCenter is not able to show you performance data older than one day for physical or virtual servers
Now, let's try to propose a simple high availability (HA) solution based on Citrix/VMware products and compare their prices. Let's suppose we have 2 (3) entry level servers where each have 2 CPUs with max 6 cores per CPU (6 CPUs total). The servers are connected to a shared disk storage. The CPU speed or memory capacity is not important now. And we require HA solution to protect our virtual machines from hardware failure. Follows the analysis:
- Citrix Essentials Enterprise (1 license = 1 server):
* XenServer - 2 licenses = 0$ (3 lic = 0$)
* Essentials Enterprise - 2 lic = 5500$ (3 lic = 8250$)
* Essentials Preffered Support (optional) - 1 lic = 1500$
* Total cost = 7000$ or 9750$ for 3 servers
* Total cost without support = 5500$ or 8250$ for 3 servers
- VMware vSphere 4 Standard Edition (1 lic = 1 CPU):
* vSphere 4 Standard - 4 licenses = 3180$ (6 lic = 4770$)
* vShpere 4 Standard 1y Gold Support - 4 lic = 1092$ (6 lic = 1638$)
* vCenter 4 Foundation - 1 lic = 1495$
* vCenter 4 1y Gold Support - 1 lic = 545$
* Total cost = 6312$ or 8448$ for 3 servers
* Support is mandatory
- VMware vSphere 4 Essentials Plus Bundle (1 lic = 1 CPU)
* Licenses for 3 hosts plus vCenter Server for Essentials plus 1y Gold Support = 3624$
* Total cost = 3624$ for 2 or 3 servers
The prices of proposed solutions are quite different. In my opinion, the most valued solution is based on new VMware product line vSphere 4 Essentials.
There are rumors that VMware is the most expensive solution. I don't think so if I check the numbers above. Citrix's solution not covered by support is cheaper then VMware's solution with support but only for 2 servers. If I would like to add third server I would have to pay another license in case of Citrix. In case of VMware, I have still one spare license so I will use it. At first glance, XenServer seems to be free of charge but the price of added value by Citrix Essentials doesn't scale as well as in case of VMware vSphere 4 Standard Edition or vSphere 4 Essentials Plus. And what is your opinion to the topic?