educative.io

Educative

Replace Active replica

generic open ended question asked :slight_smile:
There is a database which has 3 active copies. a write is replicated to 3 copies on db.
one of the db from 3 copies failed and we have to replace it.
how do you do it as we cannot stop writes.

Hi @punit
When we write on the database, the request will be sent to the backend. If the database gets corrupt while writing the request, it will be sent to the backend and replicated to the secondary databases. Then that request will be scheduled in a queue and entertained accordingly. But the user will be unaware of the database crashing and will get his results late.