On Mon, 1 Sep 2025 03:15:50 -0600 Warner Losh <[email protected]> wrote:
> On Mon, Sep 1, 2025, 3:05 AM Poul-Henning Kamp <[email protected]> wrote: > > > -------- > > Tomoaki AOKI writes: > > > > > > > > > … it would be nice to have something like 'recovery partition', as > > > > some OSes have. or at least some tiny fail-safe feature. having remote > > > > machine in some distant datacenter, booting from a flashstick is > > always > > > > a problem. > > > > I thought that is what /rescue is for ? > > > > That only works if your boot loader can read it... I've thought for a > while now that maybe we should move that into a ram disk image that we fall > back to if the boot loader can't read anything else... > > Warner Exactly. If the loader (or bootcode to kick the loader in the partition/pool) can sanely read the partition/pool to boot from, I think /rescue is enough and no need for rescue "partition / pool". But once the partition / pool to boot is broken (including lost decryption key for encrypted partitions/drives from regular place), something others are needed. And what can be chosen to boot from BIOS/UEFI firmware depends on the implementation (some could restrict per-drive only, instead of every entry in EFI boot manager table). If BIOS/firmware allow to choose "drive" to boot, rescue "drive" is useful, if multiple physical drives are available. Yes, rescue mfsroot embedded into loader.efi would be a candidate, too, if the size of ESP allows. > > -- > > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > > [email protected] | TCP/IP since RFC 956 > > FreeBSD committer | BSD since 4.3-tahoe > > Never attribute to malice what can adequately be explained by incompetence. -- Tomoaki AOKI <[email protected]>
