Hi! I'm resending original mail to this list after initial discussion with Loic Dachary so others can chime in. Loic says these rules were there to workaround certain problems on Centos 6 only and that it can be discarded now. Please, read original mail below: === We've just noticed 60-ceph-partuuid-workaround.rules. You added a patch some time ago which made these rules to be applied for DM devices too: https://github.com/ceph/ceph/commit/42ad86e14e352f2a3a33e774224f1789f268da83 The problem we've spotted and hit recently is that these rules call blkid which opens all DM devices now on uevents. However, not all DM devices are suitable for scanning as they may not be prepared fully yet. We use various flags in DM (and its subsystems like LVM) to avoid these scans and for all the rules we don't manage, there's DM_UDEV_DISABLE_OTHER_RULES_FLAG that needs to be checked in these "foreign" rules before opening such DM device (which includes running blkid). Otherwise, we may end up with errors where some DM subsystem needs to close the device or do some initialization on this device before making it public by dropping the DM_UDEV_DISABLE_OTHER_RULES_FLAG. So we need to make sure these things are in sync - the scan can't be run on all DM devices, it's controlled via DM_UDEV_*_FLAG variables. Now, when it comes to the 60-ceph-partuuid-workaround.rules, why do we need that at all? I mean, the 60-persistent-storage.rules do not whitelist DM devices, so these rules are skipped anyway and it was that way since beginning, I think. Now, I see this comment in the 60-ceph-partuuid-workaround.rules: # this is a kludge installed by ceph to fix the /dev/disk/by-partuuid # symlinks on systems with old udev (< 180). it's a stripped down # version of a newer 60-persistent-storage.rules file that hopefully # captures the same set of conditions for setting up those symlinks. So I need to get to the bottom of the problem which was resolved here. Feel free to point me to someone else if you're not the right person, but I need to understand what's behind these extra workaround rules so I can help to make it work correctly with DM devices. Thanks. -- Peter -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
