Hi all.

I have been reading a lot the last days about virtualization and about the differents flavors. But there is many information and sites where some times I get confused.

XEN use paravirtualization and use a host OS Dom0,with the hypervisor over the hardware layer.

Does XEN can be used as FULL virtualization like kvm?


KVM is FULL virtualization, and it use a host OS, isnt it?... and this is like the Virtual Machine Monitor, (the same as Xen), isnt it?


Virtual Iron is FULL virtualization too, but does it use a host or virtual machine monitor? or how is this?

I have used virtual iron, and it has a good frontend interface, you can install other OS, create disk, add/remove cpu, memory,clone servers, clone hard disk. But what is the host OS here? I read in wikip that virtual iron is XEN based but with full virtualization.

Do XEN and KVM does any frontend where you can create, remove, clone hard disk/servers. and so on?


With Virtual Iron you can have for example 3 physical server: node 0,1 and 2. for example if you have one linux running DNS server on node1 and it node files, the virtual iron move the DNS server to other node without affecting service.

Or if you have to change something on node1 , you can drag the Linux DNS server to node 0 or 2, and when finish drag again and thats it...

You can have VLANs, and use DMZ as you want.

Can ALL this be done with Xen or KVM ?


Thank you and sorry for my english, I hope you can understand what I mean.





Who has used virtual iron?

KVM and Xen use "hardware-assisted" virtualization, not "full". And Xen can do "para-virtualization" too.

Perhaps you should read a little bit more first.

Hi -

You're essentially correct.

"Virtualization" is a very, very big topic.

In addition to Xen and KVM, I would encourage you to also look at VMWare, Virtual Box ... and yes, even Microsoft technologies (including Virtual PC and Hyper-V).

IMHO .. PSM

yes

KVM is a kernel module, which turns a basic linux kernel into a hypervisor

there's citrix xenserver for xen, and RHEV, for KVM

Also, there are products like libvirt, which supports both, proxmox, convirt etc.

It's called live migration. Both KVM and Xen can do that.

possible with RHEV, never tried it with Xen

Thanks for the answer, I have now everything more clear. Right now I am installing kvm in Centos..after some problems finally I am installing the guest.


I will use this and learn all I can.


I have other doubt, the host OS is runing Centos, but as many other distros, It has many packages for example, httpd, tomcat, dns, and so on... of course I can remove these.. but is there a kind of distro only for be used for HOST OS, something light, and then you can run other guest over it... or that doesnt afect the performance?

The easiest approach is simply turn off the services you don't need or want.

For Centos, you should be able to do most of this with "chkconfig":

http://www.centos.org/docs/4/html/rh...chkconfig.html

That is what I was thinking, disable what we dont need. But I just was wondering if there wasnt any light distribution for that.. sometime like asterisknow, tribox, and so on...and maybe even the kernel doesnt modules we dont need.

Thanks.

There is a lightweight hypervisor distro:
oVirt node
and RHEV-H