Compare Xen Project and XenServer 
There is literally no reason NOT to use Xen. It just works... and it works exceptionally well! It's so easy to con figure, and it's stable. It's easy to set it and forget it. Instances can remain up for an indefinite amount of time, and run efficiently.
This hypervisor offer free resources that are in other paid hypervisors, like live migration, live storage migration, openvswitch with vxlans. It is compatible with cloud orchestrators like CloudStack and OpenStack. It supports paravirtualization, but...
Significant issues with remote access and in particular very limited web browsing capabilities in the version used by our company. As a frequent traveller its the single biggest frustration
There is literally no reason NOT to use Xen. It just works... and it works exceptionally well! It's so easy to con figure, and it's stable. It's easy to set it and forget it. Instances can remain up for an indefinite amount of time, and run efficiently.
This hypervisor offer free resources that are in other paid hypervisors, like live migration, live storage migration, openvswitch with vxlans. It is compatible with cloud orchestrators like CloudStack and OpenStack. It supports paravirtualization, but...
Significant issues with remote access and in particular very limited web browsing capabilities in the version used by our company. As a frequent traveller its the single biggest frustration
