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Can you help me with my software licensing question?
We are currently evaluating two free bare-metal virtualization product: VMware ESXi 4.0 and Citrix XenServer 5.5. While both look good on the reviews, we are curious about their licensing.
A quick glance at XenServer Installation Guide (published June 2009), I found that we have to acquire free license on annual basis. This raises a concern, what will happen if Citrix decide to stop releasing license.
Quoting from the document:
Q: The XenServer license has expired. What is going to happen?
A: If the license on a XenServer host expires or goes beyond its activation date while the system is still running, all active virtual machines continue to run as long as the host system is not disrupted. However, new VMs cannot be launched. If the host system is then disrupted (through a power failure, system restart, and so on), a Citrix Essentials for XenServer system will reverts to Citrix XenServer-level functionality when its host is restarted.
Do you think we should continue evaluating XenServer, or drop it in favor of ESXi?
EDIT: We tested further by setting the system clock on the host one year ahead. After that, we cannot boot all the VMs. So it's not Essentials license that expired, but the XenServer itself.