On Mon, Jul 10, 2017 at 10:38:38AM +0200, Lennart Poettering wrote: > On Wed, 05.07.17 13:01, David Disseldorp (dd...@suse.de) wrote: > > > Ceph relies on by-partuuid symlinks, in order to locate the journal > > partition from a given OSD partition. For details, see > > http://tracker.ceph.com/issues/19489. > > This appears way too broad, as it would apply to all LVM and all other > devices. > > It appears to me Ceph should do the same as LVM does for this, and > ship its own set of rules, and be careful to only match against the > actual devices it creates.
Ceph does not create any devices (except /dev/rbd/* but it's not the case here). Ceph block storage uses any kind of block device for its operation, be it plain partition, LUKS encrypted storage, LVM, dm-multipath devices and so on. Ceph block storage contains few parts - actual storage, write-ahead log, journal etc. Any of those parts can utilize block devices, so ceph uses symlinks to point to proper block device: # ls -l /var/lib/ceph/osd/ceph-11/block lrwxrwxrwx. 1 root root 33 Jul 10 10:51 /var/lib/ceph/osd/ceph-11/block -> /dev/disk/by-partuuid/43bdcb85-06 Nb. ceph already ships rules for autodetecting if given partition belongs to ceph (discriminating by partition type, see https://github.com/ceph/ceph/blob/master/udev/95-ceph-osd.rules ), but 'by-partuuid' links should be created by earlier udev rules - like they are for some whitelisted set of device nodes names. -- Tomasz Torcz "Never underestimate the bandwidth of a station xmpp: zdzich...@chrome.pl wagon filled with backup tapes." -- Jim Gray _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel