In replsettest1.js we do:
Between the getLastError and the dumpOplog, one more oplog entry was written. The last two oplog entries are (newest first):
The test expects no new oplog entries between getLastError and dumpOplog, so it fails:
We probably need to wait for the last oplog entry resulting from the ensureIndex call before calling getLastError. Handing off to Execution since this appears to be an intermittent failure from "Simultaneous indexing on all nodes (two phase commit)".