Resume follower API

Resumes a follower index.

Request

POST /<follower_index>/_ccr/resume_follow
{
}

Prerequisites

  • If the Elasticsearch security features are enabled, you must have write and monitor index privileges for the follower index. You must have read and monitor index privileges for the leader index. You must also have manage_ccr cluster privileges on the cluster that contains the follower index. For more information, see Security privileges.

Description

This API resumes a follower index that has been paused either explicitly with the pause follower API or implicitly due to execution that can not be retried due to failure during following. When this API returns, the follower index will resume fetching operations from the leader index.

Path parameters

<follower_index> (Required)
(string) The name of the follower index.

Request body

max_read_request_operation_count
(integer) The maximum number of operations to pull per read from the remote cluster.
max_outstanding_read_requests
(long) The maximum number of outstanding reads requests from the remote cluster.
max_read_request_size
(byte value) The maximum size in bytes of per read of a batch of operations pulled from the remote cluster.
max_write_request_operation_count
(integer) The maximum number of operations per bulk write request executed on the follower.
max_write_request_size
(byte value) The maximum total bytes of operations per bulk write request executed on the follower.
max_outstanding_write_requests
(integer) The maximum number of outstanding write requests on the follower.
max_write_buffer_count
(integer) The maximum number of operations that can be queued for writing. When this limit is reached, reads from the remote cluster will be deferred until the number of queued operations goes below the limit.
max_write_buffer_size
(byte value) The maximum total bytes of operations that can be queued for writing. When this limit is reached, reads from the remote cluster will be deferred until the total bytes of queued operations goes below the limit.
max_retry_delay
(time value) The maximum time to wait before retrying an operation that failed exceptionally. An exponential backoff strategy is employed when retrying.
read_poll_timeout
(time value) The maximum time to wait for new operations on the remote cluster when the follower index is synchronized with the leader index. When the timeout has elapsed, the poll for operations will return to the follower so that it can update some statistics. Then the follower will immediately attempt to read from the leader again.

Default values

The following output from the follow info api describes all the default values for the above described index follow request parameters:

{
  "follower_indices" : [
    {
      "parameters" : {
        "max_read_request_operation_count" : 5120,
        "max_read_request_size" : "32mb",
        "max_outstanding_read_requests" : 12,
        "max_write_request_operation_count" : 5120,
        "max_write_request_size" : "9223372036854775807b",
        "max_outstanding_write_requests" : 9,
        "max_write_buffer_count" : 2147483647,
        "max_write_buffer_size" : "512mb",
        "max_retry_delay" : "500ms",
        "read_poll_timeout" : "1m"
      }
    }
  ]
}

Examples

This example resumes a follower index named follower_index:

POST /follower_index/_ccr/resume_follow
{
  "max_read_request_operation_count" : 1024,
  "max_outstanding_read_requests" : 16,
  "max_read_request_size" : "1024k",
  "max_write_request_operation_count" : 32768,
  "max_write_request_size" : "16k",
  "max_outstanding_write_requests" : 8,
  "max_write_buffer_count" : 512,
  "max_write_buffer_size" : "512k",
  "max_retry_delay" : "10s",
  "read_poll_timeout" : "30s"
}

The API returns the following result:

{
  "acknowledged" : true
}