BTRFS and Virtual OS Installations

[SpecialEd]

For those of you who use BTRFS how do you do virtual installations of other OS's? Do you set aside a partition on your main drive or do you use a separate drive?

[GreyGeek]

Although you can use NCOW on the directory in which you plan to place your virtual drives, I recommend resizing your BTRFS partition by 60GB or so, as described by Oshunluver, creating a 60GB partition, and then formatting it with EXT4. Use that partition as the place to put your virtual drives. I did that a year or so ago and it worked beautifully. Only recently I noticed that I wasn't logging into Neon (my virtual distro) so I uninstalled QEMU & the kernel vm (I didn't use VB because the QEMU&KVM is much faster) and then used kpartition to delete the partition. I then resized the BTRFS partition to fill the drive, thus recapturing the 60GB for my BTRFS partition. It's drop dead easy and in one of his posts Oceanluver describes the whole shrinking and expanding of a BTRFS partition using the resize parameter.

[SpecialEd]

Thanks for the reply GG, I hope you and yours are well.

[oldgeek]

I have btrfs on an entire drive, am using 18.04, and have installed three distros using QEMU (aeon 19.10, neon, and manjaro kde). I have assigned 20 GB disk space and around 4GB memory (I have 16 GB altogether). Everything works as i think it should. My btrfs drive is 500 GB. This way I can see the new KDE and Kubuntu plus Manjaro, which is a fallback in case Ubuntu decides to snapp everything! I do not have a dual boot system--Windows is gone forever. I hope you are well, GreyGeek. You got me going on btrfs.

[oshunluvr]

I issue is when you use dynamically sized drives. If you use fixed size (full size) virtual drives there shouldn't be a problem.

[Thomas00]

I haven't been here for a long time (switched distribution) but when I just now thought I'd quickly check what's keeping the Kubuntu folks busy I right away stumble over GreyGeek again who's announced his retirement just before I moved on.
Well, GryGeek really good to see you are back online! I'd like to grab this opportunity to tell you that I learned a great deal from you (and others on this forum) when I got serious with Linux/Kubuntu. And like back then with BTRFS, you right away triggered my curiosity to check out QVM&KVM. :-) I use Virtualbox a lot, sometimes 4 VMs in parallel.
Wish you all the best and hope this forum (and possibly others) can enjoy your insights for many more years to come!

[GreyGeek]

Thanks, Thomas00, but I'm not really coming out of retirement. I drop by and check the post titles for grins and giggles and when I saw the one about BTRFS I couldn't resist tossing my thoughts into the ring. I'm really conservative in how I maintain BTRF, my settings in fstab, and using the fstrim and BTRFS balance commands. In four years of using BTRFS I've never had a single problem with it. I did have a hardware problem after which I decided to re-install 18.04 without QEMU and KVM. Having used KVM and VB, my own experience is that KVM is much faster and so transparent that it seems like the virtual distro was installed on the metal. IIRC, and that's been an increasingly difficult problem, along with typing problems due to tremors, the VM also used my NVidia graphics acceleration as well.

Anyway, I am now resuming my retirement...

[SpecialEd]

Who was that masked man?