proxmox-restore-vm-data provides means to build a debian package
containing a minimalistic Linux kernel and a corresponding initramfs
image for use in a file-restore VM.
Launched with QEMU/KVM, it boots in 1.6 seconds to userspace (on AMD
2700X) and has a minimal attack surface (no network stack other than
virtio-vsock, no auxiliary device support (USB, etc...), userspace
written in Rust) as opposed to mounting backup archives directly on the
host.
Since our Rust binaries are currently not fully statically linked, we
need to include some libraries into the initramfs as well. This is done
in 'build_initramfs.sh'.
A minimal /init is included as a Rust binary (init-shim-rs), doing only
the bare-minimum userspace setup before handing over control to the
file-restore daemon (see 'proxmox-backup' repository).
The debian package comes with a 'activate-noawait
pbs-file-restore-initramfs' trigger activation to rebuild the cached
initramfs when the base image shipped here updates. This is taken care
of by proxmox-file-restore.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
