Need help with virtual machine manager virbr0 connection

So I made the switch to Linux from Windows. I got some experience in the past with Linux. But only used short period time as a full desktop or on my laptop outside of VM.

My issue is I can create a VM. But when I use the local user I created, I can’t connected to bridge interface to be able to get the VM go to the internet or have connection via kvm host.

I can do that when logged in as a root and create a new VM. But the local user with admin rights and part of wheels group can’t create a virbr0 or use the created one by root.

I am receiving this error when trying to create connection in Virtual machine manager.

“network is already in use by interface virbr0”

Any tips how to overcome this?

KVM is an “Enterprise” virtualization technology.
That means that its defaults are generally optimized to be used in Production, with the security you’d expect to be in place for serious use… and that means that you won’t automatically be set up with the lax security you often find in technologies that target use on personal machines. If you want that kind of experience out of the box, you might be happier with Virtualbox or VMware Workstation and Player.

If you’re set on using and learning KVM, then these kinds of issues should be just part of the learning experience.
I suspect you aren’t following a set guide when you set up the wheel account for your User.
I recommend you follow the SLES 11 SP4 KVM documentation for learning…
Although the installation for SLES is very different compared to openSUSE, once installed almost everything can be followed step by step. If you have specific questions about what you find in this guide, go ahead and post about that

Later you can look at the SLES 12 SP3 KVM documentation, but I don’t recommend that for beginners… Some concepts are described differently, and IMO the SLES 11 documentation is more accurate.

And, also don’t recommend looking at the openSUSE LEAP virtualization documentation until you are experienced with what is in the SLES 11 documentation.

A few additional comments regarding specifics you described…
Bridge devices like virbr0 and br0 are security agnostic. Used correctly, they should be accessible by any Guest. The bridge devices themselves should never be “used” by anything other than a VM (even User accoutns) although to view and manage the devices <may> require elevated permissions. Your error can’t happen unless you’re trying to use the bridge device incorrectly.

To use a bridge device, nothing more should be required than to simply point/select to that device in the VM’s Network Properties.
Doing so exposes the features of the virtual or physical network associated with the device to the VM.
Then, from within the VM you should set up your networking as an ordinary wired adapter (typically eth0).
The Bridge device itself is completely invisible to the inside of the VM, and the OS should set up eth0 without any knowledge what is happeing outside the VM.

This is why I always recommend that a NAT bridge device be used for the first VM created by a new User… typically a NAT device will be configured with its own internal DHCP and the Guest only has to be set as a DHCP client and everything will “just work.”
On the other hand, many try to set up with br0 or create a new device with the same network bridging as a default br0… And then you can set up a DHCP client only if a DhCP server exists on the physical network which is often more than new Users can set up properly.

Maybe someone should write up a Wiki or insert in documentation a cookbook for KVM newbies describing the steps to do this…


Actually I figured it out. I connected the kvm to qemu://user but virah connected to qemu://system uri. I deleted the previous connection and VM in kvm and recreated one under qemu://system and reinstalled the OS and all working fine now.

I am nit a novice user when it comes to Linux. I tried to use CentOS at home. But it was lacking something that I couldn’t call. I never liked it. So went back to Windows. But as a Network engineer, everything we use is based on Linux on mostly RedHat. So I wanted to move that direction. I was going with Fedora, but in last second, I found some comparasion and decided to go with Open suse. So far had issues with Codecs and VM. But all figured out. I guess this is part of learning curve.

Also I am down 70% studying for RedHat Admin certification. So getting more comfortable with Linux.

Congrats on figuring it out.
The SLES 11 SP4 KVM reference I provided you should describe all that in spades…

If you’re new to openSUSE,
You might want to skim the links in a slide presentation I created recently for a presentation to my local UG…
You’ll find your codec experience listed (and why) plus other things of general interest

Am looking forward to your posting in these Forums, too.