Eduardo M KALINOWSKI wrote: > Barclay, Daniel wrote: ... >> Since GRUB hasn't loaded the kernel file yet, GRUB can't be using the kernel >> and its md driver, and therefore can't be reading the partition _as_a_RAID_ >> _volume_ (/dev/mdX), right? >> >> >> So is GRUB just reading the partition directly to get to the file system? >> > > GRUB does not know anything about RAID, so I assume this is true.
That's what I have been thinking, but I just found the message at http://www.mail-archive.com/linux-r...@vger.kernel.org/msg09712.html that says:: ... once grub2 has determined that the intended boot partition is a raid partition, the raid code takes over ... and it scans for all the other members of the raid array and utilizes whichever drives it needs to in order to complete the boot process. ... [I]t doesn't need any member of a raid1 array to be perfect[;] it will attempt a round robin read on all the sectors and only fail if all drives return an error for a given read. Is that _just_ for GRUB2 and or does the current GRUB (0.97) in Lenny also do that? >> ... is GRUB taking advantage of the fact that the RAID metadata is >> written at the end of a partition ... ... >> If so, how reliable is that? >> >> Should one put /boot on a plain, non-RAID partition on one disk and >> somehow (manually or automatically) maintain a backup /boot partition on >> the second disk, or is it fine to put /boot on a mirrored partition (so >> maintaining redundancy is automatic) and let GRUB read the partition >> directly? >> > > Again, while I haven't tried, I've seen several reports that this works. > ... So why make things more complicated and not automatic? I don't get why you're asking that. I _am_ trying to avoid the complicated and non-automatic solution (trying to check whether the simpler solution is reliable). Daniel -- (Plain text sometimes corrupted to HTML "courtesy" of Microsoft Exchange.) [F]
