[Gluster-users] Doubts re: remove-brick

[Diego Zuccato]

Il 20/11/2022 09:39, Strahil Nikolov ha scritto:
> Have you 
> checked https://staged-gluster-docs.readthedocs.io/en/release3.7.0beta1/Features/rebalance/ ? I know it's old but it might provide some clarity.
> 
> The files are removed from the source subvolume to the new subvolume.
Ok, Tks!
RH's numbering is really confusing. Why can't they simply use the 
official release number? :( And having lots of docs paywalled doesn't 
help either.

> Removed bricks do not get any writes, as during the preparation - a 
> rebalance is issued which notifies the clients to use the new DHT subvolume.
IIUC there's a mismatch between what you say and the warning I get when 
starting a remove-brick operation:
"It is recommended that remove-brick be run with cluster.force-migration 
option disabled to prevent possible data corruption. Doing so will 
ensure that files that receive writes during migration will not be 
migrated and will need to be manually copied after the remove-brick 
commit operation. Please check the value of the option and update 
accordingly.
Do you want to continue with your current cluster.force-migration 
settings? (y/n)"
If files being migrated don't receive writes (I assume "on the original 
brick"), then why is that note needed?
Most probably I'm missing some vital piece of information.

[BTW my cluster.force-migration is already off... that warning is a long 
standing issue that seems is not easily fixable]

-- 
Diego Zuccato
DIFA - Dip. di Fisica e Astronomia
Servizi Informatici
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