What to do with the 3rd Patroni node?

PostgreSQL
1

Hello!
We have 3 nodes that is running both Patroni and GlusterFS (not related to PostgreSQL).
To better understand, I will describe the GlusterFS part:
Two nodes have high storage capacity and replication is enabled between these two nodes, but the third node does not have much storage capacity and is only there as “arbiter node” (prevents split brain, hopefully).

Those 3 nodes are running Patroni as well, but the setup is weird since the 3rd node is a lot slower and barely holds the database. The 3rd node was meant for just being there to create GlusterFS quorum.

What can I do with the 3rd node regarding Patroni?
How could I benefit from the 3rd node without storing the database on it?

I thought about simply adding the 3rd node to etcd and not installing Patroni on it, but I am not sure that even makes sense for etcd.

2

Hi queried1

It would make sense to install etcd on the third node, but no Patroni or Postgres.

A third etcd node would serve much the same function as your third glusterfs - to avoid split brain by allowing the servers holding data to tell the difference between getting disconnected from the network and the other server going down.

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