[Gluster-users] shrinking a volume

[Shawn Heisey]

On 10/28/2014 1:51 PM, John G. Heim wrote:
> I want to shrink a gluster 3.2 volume. I've been reading the
> documentation at:
> http://gluster.org/community/documentation/index.php/Gluster_3.2:_Shrinking_Volumes
> 
> 
> Something that is unclear on this document is whether I will lose data
> if I follow those instructions. If I do a remove-brick and then
> rebalance, is the data copied off the removed brick to another brick?
> 
> Reading between the lines, I am thinking that I can remove the brick and
> then manually copy the data to another brick and then rebalance.

If you follow those precise instructions, you will indeed lose data.
You probably need to upgrade to at least version 3.3 before you can
follow these instructions instead:

https://access.redhat.com/documentation/en-US/Red_Hat_Storage/2.0/html/Administration_Guide/sect-User_Guide-Managing_Volumes-Shrinking.html

When I did this on my 3.3 testbed, I discovered that the removal process
uses far more disk space than it should, although the extra space is
recovered at the end of the process.  I filed a bug for this problem in
bugzilla:

https://bugzilla.redhat.com/show_bug.cgi?id=862347

Thanks,
Shawn