what happends to a write request to Mongo cluster, during Mongo primary stepdown and election

Question

I have an application constantly writing to a MongoDB replica set (for example 1 primary, 2 secondary).

I'm wondering: if I force current primary to step down, then an election for new primary could take a couple seconds to finish.

But during this election process, if there are still write requests to MongoDB, what happens to the write request?

As I understand it, any read request should be OK, but all writes have to go through the primary; but if a cluster doesn't have one, then the write request will be either queued, or dropped?

https://docs.mongodb.com/manual/reference/method/rs.stepDown/ https://docs.mongodb.com/manual/core/replica-set-elections/

Not an answer, but a cluster is usually referring to sharding in MongoDB. If you have 1 primary and 2 secondaries, you are talking about a replica set. — Rick Chen, Sep 16 '16 at 17:29

score 0 · Accepted Answer · answered Sep 16 '16 at 17:27

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You'll get an error until a new master is elected. You'd have to manage queuing in your application, otherwise dropped.

answered Sep 16 '16 at 17:27

Rick Chen

181
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thanks for replying, could you please link me to a reference? – keypoint Sep 16 '16 at 17:30

what happends to a write request to Mongo cluster, during Mongo primary stepdown and election

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