From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 27 Jan 2004 10:32:13 +0100 To: Atro.Tossavainen@helsinki.fi Cc: linuxppc-dev@lists.linuxppc.org, linux-raid@vger.kernel.org, tas@mindspring.com Subject: Re: Root Drive Mirroring and LVM. Message-ID: <20040127093213.GA10049@iliana> References: <868055F9-5045-11D8-8066-00039382032A@mindspring.com> <200401270801.i0R81HdT022197@kruuna.Helsinki.FI> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 In-Reply-To: <200401270801.i0R81HdT022197@kruuna.Helsinki.FI> From: Sven Luther Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Tue, Jan 27, 2004 at 10:01:17AM +0200, Atro Tossavainen wrote: > > Sorry about the crossposting. > > I wrote on the Yellow Dog Linux list when somebody asked about software > RAID on YDL about my experiences with it: > > >> The one really big gotcha is that the Macintosh partitioning scheme > >> can't tell the Linux kernel that certain partitions are to be > >> considered "Linux RAID autodetect" (as in x86 using the DOS partition > >> table type 0xfd). This means that you can't boot a Mac Linux system > >> directly from RAID because the kernel won't be able to autostart the > >> RAID devices. You have to work around this by creating an initial RAM > >> disk that uses the raidstart command to start your metadevices, then > >> swaps the initrd out of the way and proceeds to start the real system. > > to which Tim Seufert replied on the same list: > > > Hmmm. That would seem to be a lack in the Linux RAID code, since the > > Macintosh partition table has a vastly more flexible partition type > > field than DOS: instead of a single byte it's a string. It would mean > > breaking from the convention of using the "Apple_SVR2_UNIX" type for > > Linux partitions, but that really is just a convention as far as I know. > > Perhaps the PPC Linux developers and the Linux RAID developers should > get together on this and make some decisions so as to make it happen. Seems ok for me. Also, i guess that there are other partition types, like the amiga partitition table the pegasos boxes mostly use, which has a 32bit identifier for partition types. I guess it is the task of the RAID code to have some per partition type checking for this RAID autodetect magic. Friendly, Sven Luther ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/