Currently, I've got a Centos 5.8 host that I began playing with Xen virtual machines. It's a sandbox sort of server where I try and learn all of this virtualization stuff. In the future, I'll more than likely swith to Centos 6 and kvm, but for now, it's xen.
Searching google and the list, I can't find an explanation of how to add a second virtual NIC to a running VM when I only have one real NIC on the server. For the most part, in my searches it appears that I need a real second NIC on the server to do this. I can find a few examples, but each sort of implies it a one-to-one minimum of real hardware to virtual hardware.
So what I'm asking is "Is it possible to create a xen VM that has two virtual ethernet interfaces on a host that has only one real NIC"? I'd like to simulate a server that I can make a firewall out of and to do that would mean I need an internal and external interface. I'm attempting to create a set of firewalls in a highly available environment to test with. So far, most of the docs I find are for more complex people than I. There's concepts like virtual switches and the like that are creeping into the reading, so the more I read, the more overwhelmed I am.
Did I mention I'm still just starting to explore virtualization? If someone can provide me with a possible yes-no answer and maybe a link to documentation that might explain the way, I'll gladly do all my own grunt work.
Thanks for any and all help.
steve campbell
On Thursday 28 June 2012 20:22, Steve Campbell wrote:
So what I'm asking is "Is it possible to create a xen VM that has two virtual ethernet interfaces on a host that has only one real NIC"?
IMHO you can create an empty* bridge interface on a virtualization host.
*By 'empty' I mean no IP address and no real interfaces bridged.
By the way, there's KVM already on CentOS 5.8, so if you're going to move to CentOS 6 you'd better try KVM now. The solution I proposed earlier works for me with KVM. KVM in C5.7 was not production-ready, but it did work.
KVM absolutely requires CPU hardware virtualization extensions and requires 64bit CPU for any real production use due to RAM requirements.
Best regards, Dmitry Mikhailov.
On Fri, Jun 29, 2012 at 1:49 AM, Dmitry E. Mikhailov d.mikhailov@infocommunications.ru wrote:
On Thursday 28 June 2012 20:22, Steve Campbell wrote:
So what I'm asking is "Is it possible to create a xen VM that has two virtual ethernet interfaces on a host that has only one real NIC"?
IMHO you can create an empty* bridge interface on a virtualization host.
*By 'empty' I mean no IP address and no real interfaces bridged.
+1 This is the way I am configuring bridges and taps for my virtual network.
-- Arun Khan
On Sat, Jun 30, 2012 at 07:33:32PM +0530, Arun Khan wrote:
On Fri, Jun 29, 2012 at 1:49 AM, Dmitry E. Mikhailov d.mikhailov@infocommunications.ru wrote:
On Thursday 28 June 2012 20:22, Steve Campbell wrote:
So what I'm asking is "Is it possible to create a xen VM that has two virtual ethernet interfaces on a host that has only one real NIC"?
IMHO you can create an empty* bridge interface on a virtualization host.
*By 'empty' I mean no IP address and no real interfaces bridged.
+1 This is the way I am configuring bridges and taps for my virtual network.
Yep, creating an "empty" bridge with no physical ethernet interfaces as uplinks is normal and straight forward.
Each vif (vnic) of the Xen VM is attached to a bridge. And it doesn't matter if it's a bridge with or without uplinks.
-- Pasi
-
Arun Khan -
Dmitry E. Mikhailov -
Pasi Kärkkäinen -
Steve Campbell