Gluster users - Nov 2021 - Re-Add Distributed Volume Volume

Hi Diego,

i noticed, when i move files from broken volume to new mounted gf volume, the
folder and files are also deleted from .glusterfs directory. Thats ok right,
because there are the hardlilnks of the files, right? You wrote, that you delete
the .glusterfs Folder first and than move. I didnt try it because iam afraid of
loosing all files, if these are the hardlings. I also noticed, if i moved files
and the folder and files are also deleted in .glusterfs, the disk size didnt
change.

=> i read about hardlink and it seems that there is a remaining part of them,
thats why the free space rises, right? So i have to delete the .glusterfs
directory right and no "real" files are deleted. Thats what i
understand now by reading about hardlinks.

What do you think
thx

-- 
Am 15.11.2021 12:20:57, schrieb Diego Zuccato:
> Il 15/11/2021 06:45, Strahil Nikolov ha scritto:
> 
> > Gluster uses hard links (2 entries pointing to the same inode) and 
> > untill the hard links are not deleted, the data will be still there.
> [...]
> > The hard links are in the .glusterfs directory and after a successful 
> > move you can delete them.When I've had to move from a
"broken" volume to a newly created one, I
> first deleted the .glusterfs folders from the roots of the old bricks 
> (the volume was already broken, after all) and then moved the other 
> folders to their new home (the new volume, mounted on every node). Just 
> avoided overwriting existing files.
> This way the bricks didn't overflow.
> 
> -- 
> Diego Zuccato
> DIFA - Dip. di Fisica e Astronomia
> Servizi Informatici
> Alma Mater Studiorum - Universit? di Bologna
> V.le Berti-Pichat 6/2 - 40127 Bologna - Italy
> tel.: +39 051 20 95786
>

Hi.

If you can still move files from the broken *volume*, you don't have to 
touch .glusterfs folder: it's managed by gluster itself and that's the 
preferred way to recover (more like a transfer between two volumes that 
only accidentally share the filesystem on the bricks).

But if the vol was really broken (wouldn't start at all), the only way 
to recover would be to read the files *from the bricks*.

Those are quite different scenarios that require different recovery 
methods. Recovering from the briks is slightly more complicated, since 
you have to manually handle duplicate files, checking if they're 
actually identical or if there are differences.

Il 16/11/2021 11:14, Taste-Of-IT ha scritto:
> Hi Diego,
> 
> i noticed, when i move files from broken volume to new mounted gf volume,
the folder and files are also deleted from .glusterfs directory. Thats ok right,
because there are the hardlilnks of the files, right? You wrote, that you delete
the .glusterfs Folder first and than move. I didnt try it because iam afraid of
loosing all files, if these are the hardlings. I also noticed, if i moved files
and the folder and files are also deleted in .glusterfs, the disk size didnt
change.
> 
> => i read about hardlink and it seems that there is a remaining part of
them, thats why the free space rises, right? So i have to delete the .glusterfs
directory right and no "real" files are deleted. Thats what i
understand now by reading about hardlinks.
> 
> What do you think
> thx
> 
-- 
Diego Zuccato
DIFA - Dip. di Fisica e Astronomia
Servizi Informatici
Alma Mater Studiorum - Universit? di Bologna
V.le Berti-Pichat 6/2 - 40127 Bologna - Italy
tel.: +39 051 20 95786