Raghavendra G
2017-Jan-12 11:05 UTC
[Gluster-users] [Gluster-devel] Fwd: Behaviour of simple distributed volumes on failed bricks?
On Thu, Jan 12, 2017 at 9:20 AM, B.K.Raghuram <bkrram at gmail.com> wrote:> cc'ing devel as well for some developer insight.. > > ---------- Forwarded message ---------- > To: gluster-users <gluster-users at gluster.org> > > > I had a question on the expected behaviour of simple distributed volumes > when a brick fails for the following scenarios (as in, will the scenario > succeed for fail) : > > - New file creation if that file name hashes to the failed brick >Fails> - New file creation if that file name hashes to one of the remaining > functional brick >Succeeds - New directory creation if that file name hashes to the failed brick>Fails> - New directory creation if that file name hashes to one of the remaining > functional brick >Succeeds. Layout is spread only to the functional bricks. Non-functional bricks are not part of layout of the directory. In other words files of the directory won't be stored in non-functional bricks> - File modifications/deletions if that file name hashes to the failed brick >Fails> - File modifications/deletions if that file name hashes to one of the > remaining functional brick >Succeeds> - Directory renames/deletions if that file name hashes to the failed brick >Fails> - Directory renames/deletions if that file name hashes to one of the > remaining functional brick >Fails> > > _______________________________________________ > Gluster-devel mailing list > Gluster-devel at gluster.org > http://www.gluster.org/mailman/listinfo/gluster-devel > > -- > Raghavendra G > > <http://www.gluster.org/mailman/listinfo/gluster-devel><http://www.gluster.org/mailman/listinfo/gluster-devel> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://www.gluster.org/pipermail/gluster-users/attachments/20170112/8ca0e169/attachment.html>
Raghavendra G
2017-Jan-12 11:14 UTC
[Gluster-users] [Gluster-devel] Fwd: Behaviour of simple distributed volumes on failed bricks?
On Thu, Jan 12, 2017 at 4:35 PM, Raghavendra G <raghavendra.hg at gmail.com> wrote:> > > On Thu, Jan 12, 2017 at 9:20 AM, B.K.Raghuram <bkrram at gmail.com> wrote: > >> cc'ing devel as well for some developer insight.. >> >> ---------- Forwarded message ---------- >> To: gluster-users <gluster-users at gluster.org> >> >> >> I had a question on the expected behaviour of simple distributed volumes >> when a brick fails for the following scenarios (as in, will the scenario >> succeed for fail) : >> >> - New file creation if that file name hashes to the failed brick >> > > Fails > > >> - New file creation if that file name hashes to one of the remaining >> functional brick >> > > Succeeds > > - New directory creation if that file name hashes to the failed brick >> > > Fails > > >> - New directory creation if that file name hashes to one of the remaining >> functional brick >> > > Succeeds. Layout is spread only to the functional bricks. Non-functional > bricks are not part of layout of the directory. In other words files of the > directory won't be stored in non-functional bricks > > >> - File modifications/deletions if that file name hashes to the failed >> brick >> > > Fails >Fails mostly. However, let's say if the inode of file has been looked up when hashed-brick was up, then operations succeed even if hashed-brick goes down later. Following sequence of ops succeed: 1. hashed-brick up 2. Lookup (file) => success 3. open (file) => success (fd) 4. hashed-brick goes down 5. write/read (fd) => success Note that if the inode is cached in vfs/kernel after 2, even path based operations like stat, open, chmod etc can succeed if hashed-brick goes down immediately after successful lookup. The point is only fresh lookups fail if hashed brick/subvol is down.> >> - File modifications/deletions if that file name hashes to one of the >> remaining functional brick >> > > Succeeds > > >> - Directory renames/deletions if that file name hashes to the failed brick >> > > Fails > > >> - Directory renames/deletions if that file name hashes to one of the >> remaining functional brick >> > > Fails > > >> >> >> _______________________________________________ >> Gluster-devel mailing list >> Gluster-devel at gluster.org >> http://www.gluster.org/mailman/listinfo/gluster-devel >> >> -- >> Raghavendra G >> >> <http://www.gluster.org/mailman/listinfo/gluster-devel> > > <http://www.gluster.org/mailman/listinfo/gluster-devel> >-- Raghavendra G -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://www.gluster.org/pipermail/gluster-users/attachments/20170112/72bd5048/attachment.html>