elasticsearch- unassigned shard issue

unassigned shards: 

Shard masih tidak di assign pada mana mana node. maka data dalam shards tak available bila di query.

Sebab:

1- node down
2- free space tiada
3- dalam proses di pindahkan ke node yg lain.(ini utk pastikan bilangan node seimbang dalam semua node)

Diagnos:
- _cat/shards

- _cluster/health

- _cluster/reroute

$ curl -XPOST 'localhost:9200/_cluster/reroute' -H 'Content-Type: application/json' -d '{
    "commands": [{
        "allocate_empty_primary": {
            "index": "test-index",
            "shard": 1,
            "node": "node-1",
            "accept_data_loss": true
        }
    }]
}'
{"acknowledged":true,"state":{"cluster_uuid":"0W8o4rxdSniXsf_grVvxvQ","version":299,"state_uuid":"rHRyobYiSZ2VIOlxep0jxw","master_node":"nIzM4TPDQuS0WDHkSjEN1w","blocks":{}...

allocate_empty_primary  - utk shard primary

allocate_replica - utk shard replika 

 

- _cluster/settings

    cluster.routing.allocation.enable 

    cluster.routing.allocation.node_concurrent


 

 ref: https://www.baeldung.com/ops/elasticsearch-unassigned-shards