imageboot falls back to cp when unsquashfs is unavailable, but the build
side did not: a bare dracut_install/copy_exec aborts initramfs generation
when the binary is absent, and the capture prerequisite check refused to
capture the image at all.
Mark the initramfs copies optional and report the missing package as an
advisory rather than a hard prerequisite, so such images still build and
capture, just without the faster extraction path. Widen the EL check to
every release past el8 so future ones inherit it.
`unsquashfs` can use multiple CPU cores during image extraction, significantly reducing boot time.
For example the whole boot time from PXE to shell on a 8-core VM, from approximately 45 seconds to 20 seconds.
This PR adds `squashfs-tools` as a dependency. Since the package is smaller than 1 MB, the additional image size is justified by the performance improvement.
For backward compatibility, the existing `cp`-based extraction method is used when `unsquashfs` is unavailable, such as with images built before this change.
The extraction logic has also been moved into the common functions and is now shared between EL9, EL10, and Ubuntu.
Both untethered `squashfs` images and `confluent_multisquash` images are supported.
Images must be rebuilt to include `unsquashfs` and benefit from the faster extraction path.
The r8169 enjoys some popularity.
Also, we'd like to be able to try out diskless/cloning with
VMs, so vmxnet3 and virtio_net are handy to round that out.
Needed the real losetup to handle read-only file.
busybox wc is way too slow, use ls instead.
Explicitly make /sysroot and load xfs, as that doesn't happen implicitly.
Accept a dangling symlink as viable init, since this is the case in Ubuntu.
Update hostname and ca certificates consistent with
ubuntu standards
Markus Hilger
Jarrod Johnson
Jarrod Johnson
Vinícius Ferrão