MongoDB replica set and db.stats() We just added a node to our replica set. After the node's state switched to SECONDARY, I do
use obs
db.stats()

on both the PRIMARY node and the new SECONDARY.
               PRIMARY    SECONDARY
&quot;collections&quot; :  19          18
&quot;views&quot; :        0            0
&quot;objects&quot; :    70926        70409

Why are numbers of objects and collections different?
OK we found why there is a discrepancy.
We were able to list the collections on the secondary node with
db.getMongo().setSlaveOk()
show collections

From there, I realized the extra collection on the primary was system.profile (I'd forgotten I'd turned on the profiler) and it's 517 documents accounted for the different object counts from db.stats()