Kibana 4.2 doesn't seem to allow '.' in filter sub-aggregations. I don't see anything about '.' being special here: https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-query-string-query.html#_reserved_characters. Does that use a different syntax?
I'm trying to fuzzy-match version strings (eg 2.* vs 1.*). Maybe there's a better way? Thanks!