let’s say there are 3 nodes in my db(1 primary and 2 secondary), and primary goes down. then from the remaining 2 secondary, one of the nodes are made primary by election. we have 1 primary and 1 secondary at moment. would MongoDB spin up a new secondary if the earlier primary doesn’t recovers.
No it does not. If you are self hosting then the recovery or replacement of the failed member is on you.
If it is in MongoDB Atlas then open a ticket with MongoDB support.
For extra redundancy add two more member and go for a five member replica set. This allows up to two members to fail.
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Hi @chris
Thanks for the answer.
Also If I explicitly ask MongoDB support to spin up a new node. Then a full-resync would be done on the newly added right? And during this process, this node would be unavailable for reads if I have configured secondary read preference.
If you have a member down the support ticket would be to deal specifically with that, MongDB would recommend or take the best course of action.
If an initial sync is in progress a Secondary read will be serviced by the remaining secondaries.
Adding additional members in MongoDB Atlas, to go from 3 to 5 members for example, is your responsibility. Check configure-high-availability-and-workload-isolation for details.