- Upgrading from 0.18 requires issuing a full flush of all the indices in the cluster (
curl host:9200/_flush) before shutting down the cluster, with no indexing operations happening after the flush.
- The local gateway state structure has changed from 0.18, a backup of the state files is created when upgrading, they can then be used to downgrade back to 0.18. Don’t downgrade without using them.
- Deprecate Experimental Snappy Support (#2459)
- Deprecate Shared Gateway (#2458)
- Shard Allocation: add index.routing.allocation.require…. and cluster.routing.allocation.require…. setting (#2404)
- Indexing Slow Log (#2457)
- Upgrade to Netty 3.5.11 (#2456)
- Add types and stats to search slow log (#2455)
- Upgrade to netty 3.5.10 (#2399)
- Node Stats: Add largest thread pool count per thread pool stats (#2382)
- Setting logger levels using cluster update settings does not work (#2428)
- NullPointerException with prefix query (#2408)
- Deriving the REST status code from a failure can, very rarely, cause an infinite loop (#2402)
- Adding a type with _source or _all enabled fails, when these are disabled in index (#2394)
- Multi Match: tie_breaker should allow for floating point value (#2397)