I'm using a mongodb replica set with two nodes in different data centers.
One day, because of unknown packet drop, replica set was broken.
So I restored the replica set by removing/adding secondary node, but there is still something wrong.
Here is the status of the nodes, from the information given by rs.status() and rs.conf():
Why last heart beat is too old?
Replication with two mongodb is not working
For example, the number of documents in the collection 'letter' is not the same across the two nodes:
