Linux RHEL Virtualization

Nested Virtualization on RHV 4.3

While diving into Red Hat virtualization, I wanted to do some nested virtualization on my Intel NUC. In order to do nested virtualization on RHV 4.3 there are a few things you must configure. Please note that this feature is in tech preview currently.

First we need to check to make sure that nested virtualization is enabled on our host node. The Fedora docs have a great page for this.

In order to enable nested virtualization in RHV. You will need to pin the VM that you want to use it on to a particular host and disallow migration of that VM using live migration features. For me since this is a single NUC.

When building a new virtual machine or editing an existing one you will be looking at a screen that looks like the one below. Click on the ‘Host’ tab.

After you click on the host tab you will be looking at a screen similar to the screenshot below. You will want to pin the VM to a particular host, set the migration mode to Allow manual migration only. Once this is completed the Pass-Through Host CPU button will be enabled for use.

Now you will be able to do nested virtualization inside that particular VM. Repeat for any additional VMs you would like to have nested virtualization enabled.

Happy Nesting! – Mike

Fedora General Linux

Fedora 31 Update Review

Over the past week I updated my main machine from Fedora 30 to Fedora 31. I figured I would write a quick post about the overall experience thus far. I can say that overall the performance seems snappy than it was in Fedora 30. That being said I did run into a few bugs along the way.

The first bug I ran into was the dash-to-dock bug. After updating dash-to-dock settings would work but the dock would not appear on the desktop. I found that a updated RPM build was already available to the community and once applying the updated RPM from the software store and logging out and back in resolved my issues.

The second bug that reared it’s head wasn’t really a bug per se. I run a samba share on my main machine to share content to other machines on my main network. I went to browse my share to find it not working. Running smbtree on my machine failed to return anything but smbclient was working just fine but I saw a note about SMB1 protocol being disabled.

After a bit of digging I found that the new version of smb/nmb (4.11.0) that came with Fedora 31 had disabled SMB1 protocol by default. This older bug report lead me to the final conclusion. After updating my client’s autofs configs to add vers=3.0 everything was back in order and working.

Overall it was a great experience in comparison to some of my past major revision updates. I did have to reset my wallpaper as part of the screen was ‘torn’ but DKMS handled the nvidia kmod on the new kernel without issues, which was pleasantly surprising.