On Wed, 30 Sep 2015 15:11:35 +0200 Frank Wille <[email protected]> wrote:
> Hi, > > these days I have set up a Synology DS209j with a RAID-1 kernelized > RAIDframe, using the components /dev/wd0a and /dev/wd1a. > > All worked well, so I started to test some failure scenarios. > > Disconnecting wd0 was fine and the system boots from wd1a with > "component0 failed". > > Then I replaced wd0 with another disk, which previously also has been > auto-configured as /dev/raid0 during some tests, but is otherwise > completely different. Now the system started with /dev/raid0 > and /dev/raid1, where both showed a failed component. > > Ok, I realized my error and zeroed wd0's MBR and disklabel. But after > a reboot my RAIDframe was still auto-configured as /dev/raid1, > although raid0 no longer existed! Even disconnecting wd0 didn't > change that. RAIDframe tries really hard to remember what it was last configured as... > And, even worse, when I connect my original wd0a component again I get > raid0 with wd0a and failed component1, and raid1 with wd1a and failed > component0. > > Is it possible to change the "Last configured as..." setting on wd1 > back to raid0? Or do I have to reconstruct wd1 from wd0 now? Not easily. You can play around with nuking disklabels and stuff to eventually get things right, and use 'raidctl -C' to re-configure, but all of that is probably more effort than it's really worth. > And wouldn't it be nice to fix RAIDframe, so that a > previous /dev/raid1 is automatically configured as /dev/raid0 again, > when raid0 does not exist in the system? Or doesn't that make sense > for some reason? Imagine a system where /dev/raid0a is /, /dev/raid1e is /tmp, and /dev/raid2e is /bigdatabase. Further, suppose that raid1 'goes away', and that now /dev/raid2e is magically configured as /dev/raid1e. What happens on boot when /tmp is cleared, given that /etc/fstab hasn't changed to reflect the new location of /bigdatabase? I agree that it'd be nice to have an IOCTL for raidctl to change which device a RAID set will show up as on next reboot... It's not that hard to do -- just requires time to do a little coding. Later... Greg Oster
