Issue loading OpenZFS kernel modules in Fedora Silverblue
Issue loading OpenZFS kernel modules in Fedora Silverblue
Hello good people,
Hoping this is an appropriate place for troubleshooting questions, I'm learning Linux & OpenZFS in preparation of a server + NAS build, currently working in VMware Workstation. I have successfully setup OpenZFS on Fedora 39 and have configured my zpool using virtual disks.
Now I am looking to replicate the setup on Fedora Silverblue: setup OpenZFS, import the existing disks, then attach the zpool.
1. Import the OpenZFS repository
rpm-ostree install -y https://zfsonlinux.org/fedora/zfs-release-2-4$(rpm --eval "%{dist}").noarch.rpm
2. Confirmed zfs-fuse is not used
rpm-ostree override remove zfs-fuse
error: Package "zfs-fuse" not found
3. Layer the kernel headers
rpm-ostree install kernel-devel
4. Layer OpenZFS
rpm-ostree install zfs
5. Confirmed status
rpm-ostree status
State: idle
Deployments:
● fedora:fedora/39/x86_64/kinoite
Version: 39.20240304.0 (2024-03-04T00:39:42Z)
BaseCommit: b30269aa0e2604e24fd74596a75ee79ef77e6bc2b20f87b49d02f2796ccd3da2
GPGSignature: Valid signature by E8F23996F23218640CB44CBE75CF5AC418B8E74C
LayeredPackages: kernel-devel zfs
LocalPackages: zfs-release-2-4.fc39.noarch
6. I was expecting the next step to fail
modprobe zfs
modprobe: FATAL: Module zfs not found in directory /lib/modules/6.7.7-200.fc39.x86_64
Nevertheless, I went ahead and created the 2 zfs.conf files as described in the OpenZFS documentation.
cat /etc/modules-load.d/zfs.conf
zfs
cat /etc/dnf/protected.d/zfs.conf
zfs
7. This is where I am now stuck
I have tired a number of things such as:
i. Adding modprobe as a kernel argument similar to Silverblue using nVidia drivers
rpm-ostree kargs --append=modprobe=zfs
rpm-ostree kargs
rhgb quiet root=UUID=cbaf12f4-d5b4-4d24-83d6-83ad53730f2a rootflags=subvol=root rw ostree=/ostree/boot.1/fedora/5d2cc07d31373ad2a64ab4ed610ce5a45625bd317c1447d2947a489056a5c077/0 modprobe=zfs
ii. Installed, then disabled, rpm-ostree initramfs, continuing instead with initramfs-etc as described here
rpm-ostree initramfs-etc --track=/etc/modules-load.d/zfs.conf
rpm-ostree initramfs-etc --track=/etc/dnf/protected.d/zfs.conf
rpm-ostree status
State: idle
Deployments:
● fedora:fedora/39/x86_64/kinoite
Version: 39.20240304.0 (2024-03-04T00:39:42Z)
BaseCommit: b30269aa0e2604e24fd74596a75ee79ef77e6bc2b20f87b49d02f2796ccd3da2
GPGSignature: Valid signature by E8F23996F23218640CB44CBE75CF5AC418B8E74C
LayeredPackages: kernel-devel zfs
LocalPackages: zfs-release-2-4.fc39.noarch
InitramfsEtc: /etc/dnf/protected.d/zfs.conf /etc/modules-load.d/zfs.conf
8. zfs, zpool seem ok as I can get the help output or read the man pages, however:
zpool status
The ZFS modules cannot be auto-loaded.
Try running 'modprobe zfs' as root to manually load them.
zfs get all
The ZFS modules cannot be auto-loaded.
Try running 'modprobe zfs' as root to manually load them.
Obviously, I'm missing something due to my gaps in experience with Linux. I see that Universal Blue has incorporated OpenZFS as described on the GitHub page, so it should be possible for me to achieve this as well, I suppose.
Any pointers, documentation or advice is appreciated!
DKMS isn't supported on Silverblue. Only Kmods. So there's your problem.
https://docs.fedoraproject.org/en-US/fedora-silverblue/troubleshooting/
Even if you can get it to work, running ZFS on fedora generally is an exercise in frustration because the kernels update to newer versions than what ZFS supports anyway.
Thank you! This is the page where I discovered that I can try
rpm-ostree kargs --append=modprobe=zfs, which didn't work.
Still, as far as I understand it, ublue managed to overcome this, as they do offer a Fedora version with zfs included.
What am I missing?ublue built zfs as a kmod.
I don't use Fedora, but I have ZFS on all my Arch systems for everything (including root fs). So, I'll make a guess - is the package you installed for ZFS a DKMS kernel module, or a binary one? That's the first thing. If it's a DKMS module, I don't see anything on your output showing it was compiled, which would explain the module not loading. If it's a binary module in that package, it must be for the exact same version of the kernel that is installed - exact same. If it mismatches then you need either a different kennel or different ZFS package. In either case, you'll probably need to wire in a hook for your initramfs, but it looks that part might be ok from your output. Hope that helps, good luck. ZFS is incredibly good.
This is where my knowledge of Linux falls short.
is the package you installed for ZFS a DKMS kernel module, or a binary one?
In both Fedora and Silverblue I find the same, ZFS-related files, under
/usr/sbin/Jan 1 1970 blkzone lrwxrwxrwx. 43 root root 11 Feb 28 13:59 cache_metadata_size -> pdata_tools -rwxr-xr-x. 3 root root 24176 Jan 1 1970 fatresize -rwxr-xr-x. 3 root root 756 Jan 1 1970 fsck.zfs -rwxr-xr-x. 3 root root 15960 Jan 1 1970 fsfreeze lrwxrwxrwx. 91 root root 3 Feb 28 13:59 lvresize -> lvm -rwxr-xr-x. 3 root root 24104 Jan 1 1970 mount.zfs lrwxrwxrwx. 3 root root 22 Feb 28 13:59 named-checkzone -> ../bin/named-checkzone lrwxrwxrwx. 3 root root 24 Feb 28 13:59 named-compilezone -> ../bin/named-compilezone -rwxr-xr-x. 3 root root 32568 Jan 1 1970 nilfs-resize -rwxr-xr-x. 3 root root 69672 Jan 1 1970 ntfsresize lrwxrwxrwx. 91 root root 3 Feb 28 13:59 pvresize -> lvm -rwxr-xr-x. 3 root root 73784 Jan 1 1970 resize2fs lrwxrwxrwx. 11 root root 9 Feb 28 13:59 resize.f2fs -> fsck.f2fs -rwxr-xr-x. 3 root root 24408 Jan 1 1970 resizepart lrwxrwxrwx. 43 root root 11 Feb 28 13:59 thin_metadata_size -> pdata_tools -rwxr-xr-x. 3 root root 804 Jan 1 1970 xfs_freeze -rwxr-xr-x. 3 root root 212440 Jan 1 1970 zdb -rwxr-xr-x. 3 root root 107736 Jan 1 1970 zed -rwxr-xr-x. 3 root root 149984 Jan 1 1970 zfs -rwxr-xr-x. 3 root root 15920 Jan 1 1970 zfs_ids_to_path -rwxr-xr-x. 3 root root 15920 Jan 1 1970 zgenhostid -rwxr-xr-x. 3 root root 32472 Jan 1 1970 zhack -rwxr-xr-x. 3 root root 65400 Jan 1 1970 zic -rwxr-xr-x. 3 root root 36536 Jan 1 1970 zinject -rwxr-xr-x. 3 root root 264288 Jan 1 1970 zpool -rwxr-xr-x. 3 root root 57688 Jan 1 1970 zramctl -rwxr-xr-x. 3 root root 40720 Jan 1 1970 zstream lrwxrwxrwx. 3 root root 7 Mar 4 10:20 zstreamdump -> zstream -rwxr-xr-x. 3 root root 162208 Jan 1 1970 ztest -rwxr-xr-x. 3 root root 53384 Jan 1 1970 zvbidAlso,
ztestdoes somethingverifying concrete vdev 0, metaslab 11 of 12 ... loading concrete vdev 0, metaslab 11 of 12 ... verifying concrete vdev 0, metaslab 11 of 12 ...I assume, therefor, that OpenZFS exists, however the kernel is not loading the related module.
Binary, library or something else - how can I tell?It's worth noting OP is on Fedora Silverblue - an "immutable" distro in which the system files are typically not editable.
Unfortunately this is why I chose to run Ubuntu server. As far as I know, it's the only distro with ZFS set up by default. I wish you luck, as I run Silverblue as my desktop and would love to run it for my server too!
I chose Fedora since I'm most familiar with RedHat from my professional activities.
You wouldn’t use Silverblue on a server, you’d use Fedora CoreOS (FCOS) or CentOS Stream CoreOS (COSS). The ublue project has a FCOS derivative called ucore with options for ZFS OOTB. I use it on my server.
There’s some examples on how you’d use dockerfiles to build a ZFS module (as well as other things) from Fedora as well.
In any case, building bootable container images containing stuff like kernel modules is currently how this type of thing is done on atomic Fedora variants.