i am not sure why this is a table scan - does the _id index not yet exist because the collection "test.foo" was brand new here? this is on a slave running --notablescan:

Fri Oct 9 13:41:58 repl: sleep 2sec before next pass
Fri Oct 9 13:42:00 repl: main@localhost:27017
Fri Oct 9 13:42:00 User Exception table scans not allowed
Fri Oct 9 13:42:00 Assertion: table scans not allowed
Fri Oct 9 13:42:00 sync: caught db exception massert:table scans not allowed while applying op: { ts: Timestamp 1255110118000|1, op: "i", ns: "test.foo", o:

}
Fri Oct 9 13:42:00 repl: applied 1 operations
Fri Oct 9 13:42:00 repl: end sync_pullOpLog syncedTo: Fri Oct 9 13:41:58 2009 4acf75e6:1
Fri Oct 9 13:42:00 repl: sleep 1sec before next pass
Fri Oct 9 13:42:01 repl: main@localhost:27017