Zfs: 0.8.0 Does not install on RHEL 8 (depmod change)

[jadams]

System information

Type | Version/Name
--- | ---
Distribution Name | Red Hat Enterprise Linux
Distribution Version | 8.0.0
Linux Kernel | 4.18.0-80.el8
Architecture | x86_64
ZFS Version | 0.8.0-rc4
SPL Version | 0.8.0-rc4

Describe the problem you're observing

depmod in RHEL8 has moved from /sbin/depmod to /usr/sbin/depmod

Fixed by changing /sbin/depmod to /usr/sbin/depmod in zfs/scripts/kmodtool

Describe how to reproduce the problem

Follow Custom Package instructions, fails at rpm install nothing provides /sbin/depmod needed by zfs

Include any warning/errors/backtraces from the system logs

Error:
 Problem 1: conflicting requests
  - nothing provides /sbin/depmod needed by kmod-zfs-4.18.0-80.el8.x86_64-0.8.0-rc4.el8.x86_64
 Problem 2: package zfs-0.8.0-rc4.el8.x86_64 requires zfs-kmod = 0.8.0, but none of the providers can be installed
  - conflicting requests
  - nothing provides /sbin/depmod needed by kmod-zfs-4.18.0-80.el8.x86_64-0.8.0-rc4.el8.x86_64
 Problem 3: package zfs-dracut-0.8.0-rc4.el8.x86_64 requires zfs(x86-64) = 0.8.0-rc4.el8, but none of the providers can be installed
  - package zfs-0.8.0-rc4.el8.x86_64 requires zfs-kmod = 0.8.0, but none of the providers can be installed
  - conflicting requests
  - nothing provides /sbin/depmod needed by kmod-zfs-4.18.0-80.el8.x86_64-0.8.0-rc4.el8.x86_64
 Problem 4: package zfs-test-0.8.0-rc4.el8.x86_64 requires zfs(x86-64) = 0.8.0-rc4.el8, but none of the providers can be installed
  - package zfs-0.8.0-rc4.el8.x86_64 requires zfs-kmod = 0.8.0, but none of the providers can be installed
  - conflicting requests
  - nothing provides /sbin/depmod needed by kmod-zfs-4.18.0-80.el8.x86_64-0.8.0-rc4.el8.x86_64

[Conan-Kudo]

@behlendorf With 0.8.0, we should stop shipping our own kmodtool fork, and use the one provided by either redhat-rpm-config (RHEL) or kmodtool (Fedora/EPEL).

That should resolve the issues, I think.

[mskarbek]

In addition to that in 0.7.13 there is a problem with missing /usr/bin/python which is nonexistent in RHEL 8 so rpmbuild complains about Python scripts during build of spl packages and fails.
I didn't want to spam with a new issue about that.

[behlendorf]

@Conan-Kudo right, shipping our own versions shouldn't be necessary any more. It'd be great to get a PR open for this.

[Conan-Kudo]

@behlendorf in retrospect, we probably need it for deb/ubu builds, but we can resync with the fedora version.

I don't know if I can get to this, but I think we should do this before cutting 0.8.0.

[behlendorf]

@Conan-Kudo re-syncing with Fedora version makes good sense. This shouldn't be too tricky but it's also not going to be a trival drop in replacement. Our version still contains at least one needed feature which hasn't been accepted upstream (kmod-devel packages). There may be a few other little tweaks we need too.

While I think we should get this updated soon I don't think it needs to block 0.8.0. But it would be nice to see it in 0.8.1.

[Conan-Kudo]

@behlendorf We shouldn't need the devel packages for 0.8.0 anymore, since SPL and ZFS are in one set of module packages.

[behlendorf]

That's true, but the kmod devel package is still required to build Lustre against ZFS.

[ofaaland]

Note that this occurs only when when using the "kmod" type build which results in zfs packages which require a specific kernel.
https://github.com/zfsonlinux/zfs/wiki/Custom-Packages#kmod

If the "kABI-tracking kmod" type build is used, the issue does not occur as the redhat-provided kmodtool is used, which gets the path to depmod right.
https://github.com/zfsonlinux/zfs/wiki/Custom-Packages#kabi-tracking-kmod