Index Lifecycles

An index’s lifecycle policy specifies which phases are applicable, what actions are performed in each phase, and when it transitions between phases.

• Hot: The index is actively being updated and queried.
  • 96:1 GB of Disk to RAM ratio, requires 2x storage to provide redundancy
• Warm: The index is no longer updated but is still queried.
  • 200:1 GB of Disk to RAM ratio, requires 2x storage to provide redundancy
• Cold: The index is no longer updated and is queried infrequently. The information still needs to be searchable, but it’s okay if those queries are slower.
  • 96:1 GB of Disk to RAM ratio, if straight from hot to cold, 200:1 ratio if warm also used. 1x storage, redundancy provided by snapshot
• Frozen: The index is no longer updated and is queried rarely. The information still needs to be searchable, but it’s okay if those queries are extremely slow.
  •  Purely searchable snapshot, only metadata mounted in the cluster. 
• Delete: The index is no longer needed and can safely be removed.

For more information, see Index Lifecycles and LM Overview from Elasticsearch Documentation.