Discussion
Was like, how exactly do I run qemu on Debian in the year 2026? There's more than one entry in apt-cache. Oh, there is a wiki page
…wow! Even in the 2020s, Linux sure is still Linux!
Hey uh question when you're "emulating" x86_64 on x86_64 qemu knows to just VM and not emulate, right. It's a little confusing to me I can't seem to download just the virtualization bits without the emulator bits
virt-manager, when you try to create a VM, asks if you would rather use a "Local ISO image" or a "Existing disk image". I'm certain if I read the entire manual I'd understand how an "ISO image" and a "disk image" are totally different but wow. Linux… Linux never changes
Okay this was a silly question. Here's what I should have asked.
Redox OS distributed me a .img.zst file. I believe this is a "finished" disk image, not install media.
After un-zst'ing, the .img cannot be opened by virt-manager.
qemu has distributed to me a program qemu-img. it has a "convert" function.
virt-manager doesn't want a .img. What *does* it want, for "import existing disk image"? The manpage here mentions "qcow" and "qcow2". Does that mean it wants a qcow?
@mcc is it a disk image or is it a CDRom image?
What flavor QEMU are you using? Proxmox? Or build-it-yourself?
What qemu wants is a qcow2 format... that's the qemu equivalent of a VMDK.
@mcc Wait till you get to the rathole that is xorriso haha
@mcc ".img" usually means "raw block device dump", it's not really a file format. which… should be fine here? I've used those with this UI. you are going to make me try this out because I am really wondering what's going on. except I don't have a handy x86 machine that can virtualize things. literally all of my computers are ARM except one and that one is… very old
@mcc linux sure is linux though, in attempting to search around for this, I found possibly the most linux page of all time (do not waste time understanding this, I don't think it's helpful, it's just … illustrative) https://osbuild.org/docs/user-guide/image-descriptions/fedora-44/minimal-raw-zst/
@mcc ISO image is read-only boot media and "disk image" is mutable storage media which may or may involve a boot volume, "obviously"
@mcc The "existing disk image" case would be where you've got an existing OS install that you want to boot in the VM. The "local ISO image" would be for the case where it is install media, and you'd want a second blank block device attached to the VM for it to install onto.
@mcc uh, ISO for install media, existing disk for creating a vm around an already setup disk?
@mcc did you already find your answer?
ISO means CD/DVD rom image, an ISO9660 filesystem. Any other disk image means an image of a writable disk.
@mcc @hyc from what I’m reading zst is a file like zip but far less well supported. It could be anything inside. My first guess is the contents are like a tarball, a bunch of files though I don’t have experience to say if it only supports a single file. Maybe it’s neither a disk image or a disc image. I mean nether a disk or iso.
Maybe file -Z could help.
I feel like I’m missing something so sorry if I am.
@mcc no other suffix-like components in the name? Just zst only tells you that it's compressed with zstd.
E.g., if you had foo.tar.gz you'd know that it's a tar file that was compressed with gzip. If you only had foo.gz you have no idea what foo is. Just uncompress it and maybe `file foo` will recognize a magic number in it.
@mcc what if software but without hazing rituals
@mcc I can't remember the last time I used virt-manager with anything other than a .iso. If I had a raw disk image I'd just bring it up with command line qemu with a repeatable bash script.
@AlgoCompSynth I have a ".zst", and I'm not yet sure what it is or if I'm supposed to unpack it
@mcc @AlgoCompSynth the programme you want is `zstd`. this program was written by facebook employees. #lang_en
@mcc wow. it sure is linux.
I am pretty sure you can just do virt-manager and remain ignorant of 90% of this
@mcc if you're using a GUI on the system in question GNOME Boxes automates all the impenetrable command line options for running a VM, although I wish it had more options for configuring the networking of the VM
@mcc earlier this year I installed cockpit-machines on my Debian NUC thinking it would abstract away some of the qemu/libvirt bs. Spoiler alert, it did not.
@waffle_iron What would you consider the bs part?
@mcc I kept having to fight to get it to boot with an EFI bios and never could get it to work. The libvirt storage virtualization used by BIOS was different modules than EFI. I could never come to a solution that didn't involve me blindly editing libvirt XML files and hoping it would work.
@mcc If I understand question correctly, you need to use `enable-kvm` flag with qemu to use cpu virtualization extensions.
@dyniec Will virt-manager let me enable this in the GUI? Is virt-manager the GUI you would recommend?
@artemist @mcc @dyniec I am a newbie on using these tools but I think you also would like to have libvirt which makes it easier to configure virtual machines instead of talking qemu directly. Then virt-manager as a UI on top was really helpful. Although not without warts and things poking through layers sometimes.
@mcc you need something called `qemu-kvm` for it to actually do the virtualization instead of emulation
someone else recommended virt-manager, and i second that too
@flamingspork @mcc if anything asks for qemu-kvm it is wildly out of date. kvm support was merged into mainline qemu in version 1.0 in 2011, then ubuntu kept the package around until 13.10 in 2013.
@artemist @flamingspork According to the debian wiki, kvm has to be specially enabled because it uses a kernel module. It doesn't seem to be a separate package, but it's definitely a separate mode.
@mcc On Debian I definitely recommend using virt-manager, at least to get started. You can always use the qemu commands directly but for getting up and running and managing things virt-manager is pretty nice imo
@mcc On Arch the "just the VM bits" package is called qemu-desktop but I'm not sure what the Debian equivalent is.
@mcc I feel your pain. Have yet to get Alpine to install and update and run with Virt. Figuring why major headache, will try again eventually. But don't understand why Alipine is difficult vs MX, thought Alpine was made for that 🤷♂️