Replica Set with Master, Secondary, 3 Arbiters

Ops and Admin Replication
5

To sum up:

  1. Having more than 1 arbiter is useless / doesn’t make sense.
  2. It’s not supported nor tested.
  3. It deteriorates the majority. MongoDB replica set maintain the “majority commit point” up to date which is the latest write operation that has been acknowledged by the majority of the data bearing nodes. If the majority commit point can’t move forward, the primary will keep 100% of the versions of 100% of the data in cache which will overflow at some point (swap). Even worst, ALL the data not majority-committed will be checked by the eviction server which will make the cache purge go more and more slowly as you go. So even for a setup like a PSSAA, if you happen to lose a S, it will prevent the primary from moving the majority commit point forward and cause a big cache pressure on the 2 remaining nodes. PSAAA simply doesn’t work as the majority commit point can NEVER move forward as the majority of data bearing nodes can never be reached.

Here is an even more detailed answer from @Stennie_X.

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