Replica Set with Master, Secondary, 3 Arbiters

Ops and Admin Replication
10

Hello @Asya_Kamsky - Thanks for the clarification. I see what you are saying. For testing the same, performed the following combinations:

  1. With PSAAA -> turned off 3 Arbiters;
    Result: P became S and S remained S (Impact to RS overall)

  2. With PSA -> turned off 1 Arbiter;
    Result: P remained P and S remained S (no impact)

writeMajorityCount_MajorityVoteCount
writeMajorityCount_MajorityVoteCount1000×669 89.7 KB

While this is definitely a fetching point for a single arbiter based, this is a hypothetical situation that all three arbiter nodes would be down at the same time.

On the contrary, if the primary is also down, obviously the three node PSA cannot recover and elect a new primary with single Secondary alone alive in the ReplicaSet. However if a single arbiter is down and primary is also down, the remaining two arbiters along with Secondary, can make Secondary as primary, and hence enabling the better stability and availability for the ReplicaSet.

In both the cases, I have clarified with the images above, on writeMajorityCount being unchanged from 2 (with PSAAA and PSA). While majorityVoteCount is changed from 3 to 2 when it is PSAAA and PSA.

Thanks again and hope the above explains the better reliability with PSAAA.

Regds,
Sivakumar