[SOLVED] Downgrading the kernel for ZFS

hossbeast · 2017-06-26 02:36:27

Brand new to Arch in the last week or so.

I'm trying to install ZFS using this guide (https://wiki.archlinux.org/index.php/ZFS), I went with the archzfs repository.

The install fails because my kernel is too new, viz.

todd@euclid ~/aur
1 % uname -a
Linux euclid 4.11.5-1-ARCH #1 SMP PREEMPT Wed Jun 14 16:19:27 CEST 2017 x86_64 GNU/Linux

todd@euclid ~/aur
0 % sudo pacman -S zfs-linux
resolving dependencies...
warning: cannot resolve "linux=4.10.13-1", a dependency of "spl-linux"

The ZFS install guide says to downgrade your kernel to the appropriate version for ZFS, and points to this guide (https://wiki.archlinux.org/index.php/Do … g_packages).

However that guide doesn't seem to offer much help on downgrading the kernel itself. I can't seem to figure out how to downgrade the kernel from that page, and I'm a bit gunshy about busting my install by messing with the kernel packages.

What is the best way to go about fixing my system for a ZFS install?

Last edited by hossbeast (2017-06-29 14:44:31)

bazzawill · 2017-06-26 05:54:37

I have found myself in the same pickle without the file I need to upgrade. If you have upgraded through each kernel you should have linux-4.11.6-1-x86_64.pkg.tar.xz and linux-headers-4.11.6-1-x86_64.pkg.tar.xz in your /var/cache/pacman/pkg which you can simply install with sudo pacman -U linux-4.11.6-1-x86_64.pkg.tar.xz linux-headers-4.11.6-1-x86_64.pkg.tar.xz from the afore mentioned directory (although if you run nvidia drivers they may break). I however skipped a few kernels and so I am desperately looking for a copy of said kernels and header packages as they do not appear to be in any repo or the ALA. I did try going back to my previously working kernel and zfs but broke my nvidia drivers

bazzawill · 2017-06-26 09:08:55

So it turns out the previous versions are in the Arch Linux Archive https://wiki.archlinux.org/index.php/Arch_Linux_Archive just don't look at the last file as 4.10... comes before 4.9... in alphabetical order doh.

eschwartz · 2017-06-26 12:16:13

You might want to consider installing the dkms package for the zfs modules, which will be automatically rebuilt every time you update the kernel.

hossbeast · 2017-06-26 14:12:18

If I use the dkms zfs packages, does that mean I can use the newest kernel?

null · 2017-06-26 17:05:45

No. The problem is that there is no stable spl release for the current kernel yet. The *-git versions should work though.
Or just install the lts kernel which has a working zfs package in the archzfs repository.

see https://github.com/archzfs/archzfs/issues/118

hossbeast · 2017-06-27 05:10:38

I switched to linux-lts. There still seems to be a dependency conflict.

todd@euclid ~
0 % sudo pacman -S zfs-linux-lts
resolving dependencies...
warning: cannot resolve "linux-lts=4.9.30", a dependency of "spl-linux-lts"
warning: cannot resolve "spl-linux-lts", a dependency of "zfs-linux-lts"
warning: cannot resolve "linux-lts=4.9.30", a dependency of "spl-linux-lts"
warning: cannot resolve "spl-linux-lts", a dependency of "zfs-utils-linux-lts"
warning: cannot resolve "linux-lts=4.9.30", a dependency of "zfs-utils-linux-lts"
warning: cannot resolve "zfs-utils-linux-lts", a dependency of "zfs-linux-lts"
warning: cannot resolve "linux-lts=4.9.30", a dependency of "zfs-linux-lts"
:: The following package cannot be upgraded due to unresolvable dependencies:
zfs-linux-lts

:: Do you want to skip the above package for this upgrade? [y/N]
error: failed to prepare transaction (could not satisfy dependencies)
:: spl-linux-lts: requires linux-lts=4.9.30
:: zfs-linux-lts: requires spl-linux-lts
:: spl-linux-lts: requires linux-lts=4.9.30
:: zfs-utils-linux-lts: requires spl-linux-lts
:: zfs-utils-linux-lts: requires linux-lts=4.9.30
:: zfs-linux-lts: requires zfs-utils-linux-lts
:: zfs-linux-lts: requires linux-lts=4.9.30

hossbeast · 2017-06-27 05:11:13

And, this

todd@euclid ~
1 % sudo pacman -Q linux-lts
linux-lts 4.9.34-1

V1del · 2017-06-27 08:20:26

You should tell that to the maintainers of the zfs repo that they should either rebuild or - if possible - adjust the dependency to only check 4.9 instead of the minor number.

Mod note: Moving to AUR issues.

null · 2017-06-27 10:44:41

Sorry, my mistake. I didn't check the package but was sure to have read that the *-lts branch builds fine. So waiting (the maintainer said he will wait for approximately one to two weeks for a stable release or just patch it himself) or using *-git. I just double checked: linux=4.11.6-3 is the requirement of zfs-linux-git which is the same version as in core

hossbeast · 2017-06-28 04:41:14

I will go back to linux-4.11.5 (the "linux" package) and install zfs-linux-git. However, I guess this means that when I get a new kernel, zfs will break.

I'll try also zfs-dkms, although I really don't understand how it will mitigate the problem.

null · 2017-06-28 13:41:57

Pacman will refuse to update your kernel if the new version won't fulfil the dependencies of the zfs packages.

Those dkms packages won't work either, because this is an upstream problem. As you could try the *-git packages, the *-dkms-git packages should also work but are not stable releases!

So there are only three options:
1) wait until everything works again
2) use unstable git packages and risk breaking your system
3) use another filesystem

Last edited by null (2017-06-28 13:44:01)

eschwartz · 2017-06-28 22:29:00

Using the dkms package will mitigate the problem, because it essentially does the same job as updating the package in the archzfs repository. But as @null said, that still doesn't help if the source code itself is incompatible with the kernel and won't compile... so you should still be checking the output of pacman and the dkms pacman hook, but as a general rule of thumb dkms will mean you can upgrade the kernel more often.

bazzawill · 2017-06-29 00:53:46

I just received an update for the maintainer the zfs-Linux-git package has been updated to the latest kernel

hossbeast · 2017-06-29 03:38:35

Ok I've gone back to linux-4.11.5 and zfs-linux-git. (zfs-dkms fails with : target not found: spl-dkms=0.6.5.10)

What is the best practice as far as IgnorePkg in pacman.conf? Do I want to add "linux", as well as all the zfs packages?

null · 2017-06-29 07:17:17

Just put linux in there. As long as it is the same version as required by the zfs modules everything is alright and if zfs gets an update it will appear as a warning so you know that you probably can update your kernel again.

But remember, partially upgrades are completely unsupported and if your installation breaks because of this you won't get too much love from the community (aka you should know your way around to fix problems yourself). But I also did this every time there was more than a week waiting for the zfs updates and had no problem yet.

hossbeast · 2017-06-29 14:43:27

Yep, I will try to keep that time minimized.

eschwartz · 2017-06-30 00:24:01

The kernel package is possibly the one package that can be ignored with no danger at all -- it is completely self-contained, except for the OOT kernel modules it is associated with, and unless you try installing the 2.x kernel or something your system does not care which version of the kernel you are booted into.

In fact, I keep the kernel in IgnorePkg and manually update it (pacman -S linux linux-*) before I poweroff because FS#16702... this works quite well, you can update the kernel whenever *you* are ready.

Arch Linux

#1 2017-06-26 02:36:27

[SOLVED] Downgrading the kernel for ZFS

#2 2017-06-26 05:54:37

Re: [SOLVED] Downgrading the kernel for ZFS

#3 2017-06-26 09:08:55

Re: [SOLVED] Downgrading the kernel for ZFS

#4 2017-06-26 12:16:13

Re: [SOLVED] Downgrading the kernel for ZFS

#5 2017-06-26 14:12:18

Re: [SOLVED] Downgrading the kernel for ZFS

#6 2017-06-26 17:05:45

Re: [SOLVED] Downgrading the kernel for ZFS

#7 2017-06-27 05:10:38

Re: [SOLVED] Downgrading the kernel for ZFS

#8 2017-06-27 05:11:13

Re: [SOLVED] Downgrading the kernel for ZFS

#9 2017-06-27 08:20:26

Re: [SOLVED] Downgrading the kernel for ZFS

#10 2017-06-27 10:44:41

Re: [SOLVED] Downgrading the kernel for ZFS

#11 2017-06-28 04:41:14

Re: [SOLVED] Downgrading the kernel for ZFS

#12 2017-06-28 13:41:57

Re: [SOLVED] Downgrading the kernel for ZFS

#13 2017-06-28 22:29:00

Re: [SOLVED] Downgrading the kernel for ZFS

#14 2017-06-29 00:53:46

Re: [SOLVED] Downgrading the kernel for ZFS

#15 2017-06-29 03:38:35

Re: [SOLVED] Downgrading the kernel for ZFS

#16 2017-06-29 07:17:17

Re: [SOLVED] Downgrading the kernel for ZFS

#17 2017-06-29 14:43:27

Re: [SOLVED] Downgrading the kernel for ZFS

#18 2017-06-30 00:24:01

Re: [SOLVED] Downgrading the kernel for ZFS

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