Rebalance

Rebalance database shards {#put-bdbs-actions-rebalance}

PUT /v1/bdbs/{int: uid}/actions/rebalance

Distributes the database's shards across nodes based on the database's shard placement policy. See [Shard placement policy]({{<relref "/operate/rs/databases/memory-performance/shard-placement-policy">}}) for more information about shard placement and available policies.

Required permissions

Request {#put-request}

Example HTTP request

PUT /v1/bdbs/1/actions/rebalance

Dry-run example:

PUT /v1/bdbs/1/actions/rebalance?only_failovers=true&dry_run=true

URL parameters

Query parameters

Response {#put-response}

• If dry_run is false, returns an action_uid. You can track the action's progress with a [GET /v1/actions/<action_uid>]({{<relref "/operate/rs/references/rest-api/requests/actions#get-action">}}) request.

• If dry_run is true, returns the balanced shards' blueprint.

  You can rearrange shards according to this blueprint if you use it in the shards_blueprint field of a [rearrange database shards]({{<relref "/operate/rs/references/rest-api/requests/bdbs/actions/optimize_shards_placement#put-bdbs-rearrange-shards">}}) request.

  You should also pass the rebalance shards' cluster-state-id response header as a request header of the rearrange database shards request to make sure the optimized shard placement is relevant for the current cluster state. The cluster will reject the update if its state changed since the optimal shards placement blueprint was generated.

Example response

If dry_run is false:

{
    "action_uid": "21ad01d5-55aa-4ec6-b5c0-44dc95176486"
}

If dry_run is true:

[
  {
    "nodes": [
      {
        "node_uid": "3",
        "role": "master"
      },
      {
        "node_uid": "1",
        "role": "slave"
      }
    ],
    "slot_range": "5461-10922"
  },
  {
    "nodes": [
      {
        "node_uid": "3",
        "role": "master"
      },
      {
        "node_uid": "1",
        "role": "slave"
      }
    ],
    "slot_range": "10923-16383"
  },
  {
    "nodes": [
      {
        "node_uid": "3",
        "role": "master"
      },
      {
        "node_uid": "1",
        "role": "slave"
      }
    ],
    "slot_range": "0-5460"
  }
]

Status codes {#put-status-codes}