[SOLVED] ZFS dkms build fail, one server ok, one server not ok


Renowned Member
Jul 29, 2013
Have 2 servers running ZFS and Proxmox

Long story short, accidentally ran an update on wrong server and now getting

Error! Bad return status for module build on kernel: 4.15.15-1-pve (x86_64)
Consult /var/lib/dkms/zfs/ for more information.

This error repeats for every kernel i have installed.

I researched a bit an only came across this old thread:


Which essentially if i understand it, zfs-dkms is not required or needed for zfs support on proxmox and in fact should not be present?

The thing that confuses me is I have another Proxmox (Debian Stretch Up to date)
That HAS zfs-dkms and does not throw these errors. I dont know what to do and I cannot reboot this server until I am sure it will come back up.
Hi, thank you for your response.

Ok, I think I understand what is happening.
The servers were both Debian upgraded to Proxmox.
Debian had zfs-dkms running with debian kernel.

Debian kernel was not removed at the end of installation, and wont be.

Once Proxmox was installed the previously working kernel (4.9.0-8-amd64, x86_64) zfs-dkms modules continued as normal (unused while booted on proxmox kernel), but on installation of proxmox kernel, dkms trys to build for the proxmox kernel and fails, I guess because the modules are built in??? This also goes for spl as well I am guessing? My previous question about this was answered above.

Purging and reinstalling/reinitiallzation of zfs/spl-dkms does remove the old modules, but for some reasons, because it fails building them for the pve kernels it doesn't rebuild them for the debian kernel either.

Wish I understood a bit more to make it a bit more clear but I was able to rebuild the modules for the debian kernel by doing a dkms build just for them.

Broken Server Here
dkms status
spl, added
zfs, added

4.9.0-8-amd64 is the debian kernel that happens to be installed.

dkms install -m spl -v -k 4.9.0-8-amd64
dkms install -m zfs -v -k 4.9.0-8-amd64

OK server here
dkms status
spl,, 4.9.0-8-amd64, x86_64: installed
zfs,, 4.9.0-8-amd64, x86_64: installed

After I manually fixed them, now when installing another debian kernel, the debian kernel also properly gets dkms modules built for it.

apt install linux-image-4.9.0-7-amd64 linux-headers-4.9.0-7-amd64
dkms status
spl,, 4.9.0-7-amd64, x86_64: installed
spl,, 4.9.0-8-amd64, x86_64: installed
zfs,, 4.9.0-7-amd64, x86_64: installed
zfs,, 4.9.0-8-amd64, x86_64: installed

So not 100 percent sure what happened but everything seems ok now. DKMS works fine for the kernels its supposed to and doesn't bork anything when its not supposed to. :)

Going for a reboot. Thanks for the help.

Rebooted just fine. <3 Proxmox Team
Last edited:


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