XEN on GENTOO ... does it work?

obiwanbill · n00b Joined: 10 Feb 2021 Posts: 7

Ok, I am new to Gentoo, I started less than a month ago.

I have Gentoo installed on BM (BareMetal) booting via EFI_Stub into a ZFS root. Yes, I know, not the simplest thing to do for my first Gentoo install. I created a ZFS BOOT Mirror, my EFI partition is "mirrored" and I can break the mirror and the system still boots. It works and I am SUPER happy with it.

OK, that part of the project is complete, now I want to get XEN working. I have 50+ VMs I want MIGRATE to this new box and I am having trouble getting XEN to work.

The Stage3 I installed was 'No Multilib'. My hope was I could build just 64bit PVMs. I don't want HVM support and I don't want x32bit OS installs. Obviously I am reading from the Gentoo handbook and other accompanying articles others have wrote but it seems like the XEN docs are "lean".

Can I do this? Or am I trying to do something impossible. It wouldn't be the first time.
Any feedback from Gentoo installs using XEN successfully would be appreciated.

Bill

UPDATE: No worries ... I got it! With Stage3 Multilib, EFI boot, ZFS and XEN!
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Duran Duran, "You got to believe it will be alright in the end!"

obiwanbill · n00b Joined: 10 Feb 2021 Posts: 7

OK, I got XEN installed in a VM (VirtualBox) and it's working there with Stage3 MultiLib

I can do this ...
$ xl list
Name ID Mem VCPUs State Time(s)
Domain-0 0 2873 2 r----- 24.7

PERFECT!

I originally tried to get it working on BM (BareMetal) and I can't get XEN installed properly there.
I am at the point where I do this ...

$ time emerge --ask app-emulation/xen app-emulation/xen-tools -v --quiet

... and what should happen is ... the above packages are compiled and added to my system and a "xen.efi" is created and stored here ...

$ ls -lha /boot/efi/gentoo/xen-4.13.2.efi

On my VirtualBox VM Stage3 MultiLib, it works!
On my BM with Stage3 NoMultiLib... no joy! :-(

I am not sure how to fix this. I am reading here ... https://wiki.xenproject.org/wiki/Xen_EFI
... and they specifically say ... "Once built, make install-xen will place the resulting binary directly into the EFI boot partition"

Now, I didn't run "make install" in either case (on VM or on BM).
I think this is a problem with the emerge script. Where can I report this? Or, can I fix it myself?

Thanks in advance,

Bill
_________________
Duran Duran, "You got to believe it will be alright in the end!"

pjp · Administrator Joined: 16 Apr 2002 Posts: 20152

I don't see the "Once built" quote in that document.

According to the Xen Project page, the team uses the #gentoo-virtualization IRC channel, so that may be your next best route. Otherwise there is bugs.gentoo.org.
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obiwanbill · n00b Joined: 10 Feb 2021 Posts: 7

You are right. It's not on that specific page I quoted above ... there is a link on that page "EFI.html" ... http://xenbits.xenproject.org/docs/unstable/misc/efi.html

Anyway, whatever. I have a new plan ... Build Gentoo with ZFS, EFI BOOT and XEN in ...

1. a VirtualBox (VB) VM container (MultiLib)
2. a VB VM container (NoMultiLib)
3. a VB VM container (Hardened, NoMultiLib)

Those are the 3 types of Gentoo installations I am interested in anyway.
I will manage and maintain those and that way, if I discover any "issues", I am right on top of it.

I want to make this Gentoo solution work ... if I can't, I guess I just give up on Source Based Distributions. It looks to me like Gentoo is the most supported "source based" distribution and I can list all of the benefits of going this way. Though, I would be preaching to the choir. What other options do I have? Linux from Scratch? Hmm ... that sounds like a rabbit hole that I don't want to go down.

By doing this Gentoo thing, I am beginning to see what the Binary Distributions are "protecting me from". Now, I have a new appreciation for their efforts.

Oh well ... I'm just like all humans ... " I don't appreciate what I had, till I lose it"

Bill
_________________
Duran Duran, "You got to believe it will be alright in the end!"

NeddySeagoon · Posted: Tue Feb 16, 2021 12:15 pm Post subject:

obiwanbill,

XEN used to work but its been a while since I used it.
If its in the repo and broken, that's a bug. It needs to be fixed or removed.
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Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

obiwanbill · n00b Joined: 10 Feb 2021 Posts: 7

I am in the process of fully testing XEN on Gentoo ... I installed "xen" and "xen-tools" ...

1. With Stage3MultiLib ... It does install properly ... I am still going through the process of building/migrating DOMUs, etc
2. With Stage3NoMultiLib ... I haven't got it to installed properly yet. (I am still working on this)
3. WIth Stage3 Hardened ... I want to try this too. (Not tested yet) (Though, if NoMultiLib won't install properly ...)

Maybe it did work at one point? NoMultiLib should work according to this thread ... https://bugs.gentoo.org/351648
Maybe it's just me? I am no Gentoo expert. I just started on Gentoo last month.

Anyway, I'll keep plugging away because this is something I want to make work. Once I get this working to my satisfaction I will add it to your Wiki. I want to contribute here.

Bill
_________________
Duran Duran, "You got to believe it will be alright in the end!"

NeddySeagoon · Posted: Tue Feb 16, 2021 2:53 pm Post subject:

obiwanbill,

Tell us about your problems and pastebin logs.
Just your Gentoo problems. :)
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

obiwanbill · n00b Joined: 10 Feb 2021 Posts: 7

Yes, sir! On it!!

I can get Gentoo stage3 MultiLib working with XEN ... no problems here.
However, my goal is to ditch all the "x32 bit stuff" and build a system with just "x64 bit stuff."

With Gentoo stage3 NoMultiLib & Hardened, basically my problem is this, ...
1. I can build a working Gentoo system w/EFI BOOT (NO GRUB) and ZFS. I am happy.

2. I recompile my kernel to enable XEN fuctionality
3. I "emerge" xen and xen-tools. No errors.
4. At this point, I should look here and see ... I do (We are good)
$ ls -lha /boot
...
xen-4.13.2.gz
xen-4.13.gz
xen-4.gz
xen.gz

5. And I should also look here and see ... No Joy

$ ls -lha /boot/efi/gentoo
xen-4.13.2.efi <- This file is not being created when I use Stage3NoMultiLib & Hardened

Now, did I try uncompressing xen-4.13.2.gz and using that to BOOT my system? Yes. It doesn't work
All those *.gz files above are exactly the same.
xen-4.13.2.efi ... is different.

Sure, the easy solution is ... use "Gentoo stage3 MultiLib".
If that's "best practice" for someone who wants to install XEN or KVM or whatever, fine, I will do it.

Bill
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Duran Duran, "You got to believe it will be alright in the end!"

mgsouth · n00b Joined: 09 Jun 2024 Posts: 1

Yeah, an old unsolved thread. For anyone else who stumbles upon this...

Buried in the build log (instead of emerge, run