Hello, CentOS-virt list. The institution where I work has been donated some older IBM BladeCenters with IBM's LS-20 blade servers installed. These LS-20's are equipped with Opteron 275 processors (dual-core, dual-socket). In researching my virtualization options, I initially wanted to do oVirt, but after thoroughly investigating, it appears that oVirt, being based on KVM, will not work due to the Opteron 275 not supporting AMD-V virtualization extensions. So, further investigation showed that Xen4CentOS, using paravirtualization, should be supportable. So I'm looking for advice on deployment, including some pointers to some howtos or other documents on how to go about setting up a moderately large virtualization farm with Xen4CentOS on up to 200+ LS-20 blades, most of which have smallish internal storage, but with iSCSI connectivity to an EMC SAN; the deployment would start small and would grow as needed. I'm looking for the ability to do HA-type things, live migration, etc, to replace an aging VMware ESX setup. Windows guests are not a requirement. Pointers to solid VM management tools, especially for the HA and live migration options, would be nice. Purchasing upgraded blade servers isn't really an option for us at this time. (Now, if you or your organization wanted to donate some HS-21's or later, we would be glad to accept them; we are a 501(c)(3) not-for-profit public foundation...... :-) and then I could run oVirt).