Mandi! Alwin Antreich In chel di` si favelave...
I'm not a ceph expert, but solution iii) seems decent for me, with a little overhead (a readlinkk and a stat for every osd start). However you like it. But to note that in Ceph Nautilus the udev rules aren't shipped anymore.
Ok. I make a note.
But still i don't understood why, if i have: and: (so, journal partition group-owned by 'disk' and 'ceph' user in group 'disk'), still i have permission access. The ceph-osd process reset group ownership on runtime? In Luminous udev is handling all of that, see 95-ceph-osd.rules.
No, sorry, evidently i'm not explaining myself correctly.
I've added the 'ceph' user to group 'disk':
root@capitanmarvel:~# LANG=C id ceph uid=64045(ceph) gid=64045(ceph) groups=64045(ceph),6(disk)
and journal devices are group-owned by 'disk' and have read and write permission for the group (660):
brw-rw---- 1 root disk 8, 6 ago 28 14:38 /dev/sda6
So, because user 'ceph' are in group 'disk', and group 'disk' have read and write permission to the device, i can ACTUALLY read and write to the device. But is not the case.
So, seems to me that 'ceph-osd' process ''reset'' group membership and ignore the 'disk' group. Note, that if i 'su' to ceph, i can read the disks: The ceph-osd process runs with user and group ceph and this is why it wants
On Tue, Sep 03, 2019 at 05:42:22PM +0200, Marco Gaiarin wrote: the group on the disk to be ceph as well. ps xa -o user,group,command | grep ceph-osd You would need to change the service template and alter the setgroup to 'disk' or 'ceph' to make it work. -- 8< -- CGroup: /system.slice/system-ceph\x2dosd.slice/ceph-osd@1.service └─7643 /usr/bin/ceph-osd -f --cluster ceph --id 1 --setuser ceph --setgroup ceph -- 8< -- I still recommend to go with an extra SSD and spare the hassle. -- Cheers, Alwin