Major - P3 From https://github.com/mongodb/mongo/blob/r3.1.8/src/mongo/s/chunk_manager.cpp#L173
ChunkManager::ChunkManager(const CollectionType& coll)
: _ns(coll.getNs().ns()),
_keyPattern(coll.getKeyPattern()),
_unique(coll.getUnique()),
_sequenceNumber(NextSequenceNumber.addAndFetch(1)),
_chunkRanges() {
_version = ChunkVersion::fromBSON(coll.toBSON());
}
This looks suspicious as the config.collections does not contain any information about the highest (or any for that matter) chunk version of the collection.