If I deploy a MongoDb replica set across only 2 data centers, if one entire data center fails, can there be automatic failover to the other data center?
Consider the situation where 1 data center has a primary, secondary and an arbiter, and the second data center has 2 secondary members. Essentially, a 5 member replica set.
If data center 2 goes down, there will still be 3 members in the replica set in data center 1. That is great.
In reverse, if data center 2 remains up and data center 1 goes down, there will only be 2 members left out of the 5 member replica set. That is not enough to have either secondary vote themselves to become primary.
Is that correct? If not, what am I doing wrong.
If this isn't possible, please let me know so I can explore other options.
Adding a third data center to house the arbiter is not an option.