[Gluster-users] Arbiter

[Diego Zuccato]

Il 08/02/2022 12:17, Karthik Subrahmanya ha scritto:

> Since there are 4 nodes available here, and based on the configuration 
> of the available volumes (requested volume info for the same) I was 
> thinking whether the arbiter brick can be hosted on one of those nodes 
> itself, or a new node is required.
We're using replica 3 arbiter 1, with quorum balanced between the 3 
servers. No need for an extra server.

When we will add a 4th server, there'll be a lot of brick juggling 
(luckily they're connected by IB100 :) ) . The simplest thing you can do 
to balance load across 4 servers i laying down data as:
S1  S2  S3  S4
0a  b0  q0  1a
1b  1q  2a  2b
2q  3a  3b  3q
... and so on: it requires adding 8 disks at a time, 2 per server -- as 
long as you have enough blocks *and inodes* available on an ssd for 
metadata.

Hope the layout is clear: Xa and Xb are the replicated bricks, Xq is 
quorum brick for bricks Xa  and Xb.

For a 3 servers setup the layout we're using is
S1 S2 S3
0a 0b 0q
1a 1q 1b
2q 2a 2b

HIH.

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