I'd like to have different server instances connect to isolated pools of secondaries within my recordset. For example, suppose I have Primary "P" and Secondaries "S1" to "S4". I'd like to have:

Rails server 1 connects to P, S1, S2
Rails server 2 connects to P, S3, S4

The reason for this is that Rails server 2 can be something like DelayedJob which has a high load of read queries, but I can tolerate some slowness on the DB side, while server 1 is my mission-critical webserver.

Please let me know if this is possible on Mongoid 3.x as well.