On March 31, steven.rodenburg@planet.nl wrote: > Subject : Raid-5 autodetection problem > OS : Suse 7.3 for Sparc64 > Kernel : 2.4.19-pre4 > Hardware: Sun Ultra10 512MB RAM, 1x 20GB SUN Ide HD (/dev/hda), 3 x > scsi-HD in software RAID-5 config (/dev/md0 and /dev/md1) > attached to a Tekram DC390U2B Ultra2 controller. > Severity: I need a drink... > > > Hello, > > I have a problem with my SUN Ultra10 machine. > I have 3 scsi-disc's connected to a Tekram scsi-controller (sym53c8xx > driver) > i boot from the onboard IDE disk /dev/hda > > The scsi-disc's are all part of a perfectly working Raid-5 array > i copied the contents of the IDE disk to /dev/md0 > i modified the, to the array copied, /etc/fstab to say that / sits on > /dev/md0 > > All drivers are built in to the kernel > Made a new SILO entry with root=/dev/md0 so i can switch from booting > with root on the IDE disc and on the Raid5 array. > > The problem is that the array is detected but not in time (too late) Raid Auto-detect only works for ms-dos style partition tables. You probably aren't using those partition tables on a Sparc... The detection that *is* working is probably an init.d script running raidstart. But you don't really need autodetect. Simply add md=0,/dev/sda1,/dev/sdb1,/dev/sdc1 to your SILO boot line and it should work fine. > > Oh, by the way. Does anyone know why the kernel switches raid5 cache > buffer size like that ? The stripe cache size must match the size of requests that are being received by the raid5 driver. When the request size changes the cache is flushed and rebuilt. Once a filesystem is successfully mounted the request size stabilises. NeilBrown - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html