Backups are different from "origin" and replicated server


I have a server which is used in my application and yet another server which is replicated from the first one (XDCR).

When I perform a full backup (cbtransfer) from origin server it’s always several MBs bigger in comparison to backup done from replicated database. Initially I thought it’s just some subtle differences in compression, maybe compaction, etc.

But one day I’ve created a bucket from “smaller” backup and several thousand documents were missed.

So there are two problems:

  1. Records are missed on replication.
  2. Because of above I’m forced to setup backup on origin server which affects performance.

Did you face such a problem before? What could be a reason? How do I resolve it?

Thank you very much in advance for ANY suggestions.