Hi, Wido den Hollander wrote: > Aren't snapshots something that should protect you against removal? IF > snapshots work properly in CephFS you could create a snapshot every hour. Are you talking about the .snap/ directory in a cephfs directory? If yes, does it work well? Because, with Hammer, if I want to enable this feature: ~# ceph mds set allow_new_snaps true Error EPERM: Snapshots are unstable and will probably break your FS! Set to --yes-i-really-mean-it if you are sure you want to enable them I have never tried with the --yes-i-really-mean-it option. The warning is not very encouraging. ;) > With the recursive statistics [0] of CephFS you could "easily" backup > all your data to a different Ceph system or anything not Ceph. What is the link between this (very interesting) recursive statistics feature and the backup? I'm not sure to understand. Can you explain me? Maybe you test if the size of a directory has changed? > I've done this with a ~700TB CephFS cluster and that is still working > properly. > > Wido > > [0]: > http://blog.widodh.nl/2015/04/playing-with-cephfs-recursive-statistics/ Thanks Wido for this very interesting (and very simple) feature. But does it work well? Because, I use Hammer in a Ubuntu Trusty cluster nodes, and in a Ubuntu Trusty client with 3.16 kernel and cephfs mounted with the kernel module client, I have this: ~# mount | grep cephfs # /mnt is my mounted cephfs 10.0.2.150,10.0.2.151,10.0.2.152:/ on /mnt type ceph (noacl,name=cephfs,key=client.cephfs) ~# ls -lah /mnt/dir1/ total 0 drwxr-xr-x 1 root root 96M May 12 21:06 . drwxr-xr-x 1 root root 103M May 17 23:56 .. drwxr-xr-x 1 root root 96M May 12 21:06 8 drwxr-xr-x 1 root root 4.0M May 17 23:57 test As you can see: /mnt/dir1/8/ => 96M /mnt/dir1/test/ => 4.0M But: /mnt/dir1/ (ie .) => 96M I should have: size("/mnt/dir1/") = size("/mnt/dir1/8/") + size("/mnt/dir1/test/") and this is not the case. Is it normal? -- François Lafont _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
 |