Re: VMWARE/ESXi Linux

In article <vio70q$e1fp$1@dont-email.me>,
Arne Vajhøj  <arne@vajhoej.dk> wrote:

On 12/3/2024 3:24 PM, Lawrence D'Oliveiro wrote:

On Tue, 3 Dec 2024 09:40:40 -0500, Arne Vajhøj wrote:
 

If you look at what is available and what it is used for then you will
see that what is labeled type 1 is used for production and what is
labeled type 2 is used for development. It matters.

 
What people discovered was, they needed to run full-fat system management
suites, reporting tools, backup/maintenance tools etc on the hypervisor.
In other words, all the regular filesystem-management functions you need
on any server machine. So having it be a cut-down kernel (“type 1”) didn’t
cut it any more -- virtualization is nowadays done on full-function Linux
kernels (all “type 2”).

>
Having a full host OS is very nice for a development system with a few
VM's to build and test various stuff.
>
It does not scale to a large production environment. For that you need
central management servers.

There are some very senior engineers at Google and Amazon who
run the largest VM-based production environments on the planet
and they disagree.  There, VMs run under a "full host OS."

ESXi has the vSphere suite of products. For many years the basic ESXi
was actually free and customers only paid for the advanced vSphere
stuff.
>
For KVM there are many products to choose from. Redhat has
Redhat OpenShift Virtualization (it used to be Redhat Virtualization,
but it came under the OpenShift umbrella when containers took
off). The big cloud vendors that may be managing millions of
servers must have some custom tools for that. You gave a link
to someone switching to the OpenNebula product. Proxmox VE is
another option. Lots of different products with different
feature sets to match different requirements.

It's unclear what you think that KVM is.  KVM requires a
userspace component to actually drive the VCPUs; that runs under
Linux, which is a "full host OS."  At least Google uses the same
management tools to drive those processes as it uses for the
rest of its production services (e.g., borg, etc).  The
userspace component for GCP is not QEMU, but rather, a Google
authored program.  However, it is in all-respects just another
google3 binary.

- Dan C.