Index settings

Index level settings can be set per-index. Settings may be:

Static
They can only be set at index creation time or on a closed index, or by using the update index settings API with the reopen query parameter set to true (which automatically closes and reopens impacted indices).
Dynamic
They can be changed on a live index using the update index settings API.

Warning

You can change any documented index settings on closed indices. However, changing undocumented index settings on closed indices is unsupported and might result in errors.

Settings are available for the following modules:

History retention
Control the retention of a history of operations in the index.
Index
General settings that affect the behavior of indices.
Index shard allocation
Control where, when, and how shards are allocated to nodes.
Indexing pressure
Configure indexing back pressure limits.
Merge
Control how shards are merged by the background merge process.
Similarities
Configure custom similarity settings to customize how search results are scored.
Slowlog
Control how slow queries and fetch requests are logged.
Store
Configure the type of filesystem used to access shard data.
Time series
Configure the backing indices in a time series data stream (TSDS).
Translog
Control the transaction log and background flush operations.