On 06/17/2015 03:28 AM, Mihamina Rakotomandimby wrote: > > MMmmm, I really thought ESX was in some way a RHEL derivative but when > reading > http://www.v-front.de/2013/08/a-myth-busted-and-faq-esxi-is-not-based.html > it is clearly not... Older ESX had an RHEL 3-based service console; ESXi does not. Logged in to one of my ancient ESX 3.5 hosts: [root at esx1 root]# vmware -v VMware ESX Server 3.5.0 build-604481 [root at esx1 root]# cat /etc/redhat-release Red Hat Enterprise Linux ES release 3 (Taroon) [root at esx1 root]# The relationship of the service console to the vmkernel is somewhat similar to the relationship of the DomO to the Xen hypervisor, or DOS and old NetWare 3; the vmkernel itself, along with all of its loadable modules, is not in any way shape or form 'based' on RHEL; RHEL is just used to manage the vmkernel system as a 'service console.' This is much like how that Windows 386 (including 3.x, 95/98/ME) was not based on DOS (read 'Unauthorized Windows 95' by Andrew Schulman to verify) but uses DOS services in a warped fashion (Windows calls a DOS INT which is hooked by an illegal instruction 'thunk' back to the 386 mode VMMkernel which is the actual Windows Operating System kernel......). With ESXi, VMware wrote their own CLI service console, and did away with RHEL as the service console. But to address the direct question of the OP, I use KVM for many things, but I have older hardware in quantity on which I'll likely run Xen4CentOS with paravirtualized guests, since the processors in these blades do not have hardware virtualization extensions (early Opteron, but still very serviceable for what we want to do). Too many LS20 blades (about 200) to upgrade them all right now without either donations or other funding (but if anyone wanted to donate some IBM BladeServer HS21's or newer I would not turn down the donation, and we are a 501(c)(3)...... :-) ).