[Gluster-users] gluster replica 3 with third less powerful machine

[Diego Zuccato]

Il 20/10/20 15:53, Gilberto Nunes ha scritto:

> I have 3 servers but the third one is a very low machine compared to the
> 2 others servers.
How much RAM does it have?

> How could I create a replica 3 in order to prevent split-brain, but tell
> the gluster to not use the third node too much???
You could have it host just arbiters in a "replica 3 arbiter 1" volume.
I currently use a VM in this role, but it needs at least 8GB RAM to
avoid OOM (it handles 26 arbiters, so you probably can get away with
less if you have less bricks). My VM also have 8 CPUs to reduce the time
needed for resync.

Remember that backing filesystems for arbiters should be tweaked for
allowing a lot of inodes. I formatted my XFS volumes with
mkfs.xfs -i size=512,maxpct=90 /dev/sdXn
to allow up to 90% for inodes (instead of the usual 5%) => a single fs
can handle multiple arbiter bricks.

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