Hi teachers and students,
I have a question about Rolling Upgrade after watching the “Setting Up a Sharded Cluster” lesson.
If I have understood the previous lessons, we must be a little bit more careful, don’t we ?
Because, to apply the new configuration, we turn off the node2 (by calling db.shutdownServer()).
And we restart it with mongod -f <conf_file>
Then we do the same with the node3. But when we stopped node2, if we exceed the configured timeout, another election will take place and maybe node3 just becomed a primary.
And in this case we have to manage node 1 (becomed secondary) and finally node3.
Do you agree with this or am I wrong ?
Thanks a lot for your answer