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will be released for this version. For the latest information, see the
current release documentation.
Create follower API
editCreate follower API
editCreates a follower index.
Request
editPUT /<follower_index>/_ccr/follow?wait_for_active_shards=1 { "remote_cluster" : "<remote_cluster>", "leader_index" : "<leader_index>" }
Prerequisites
edit-
If the Elasticsearch security features are enabled, you must have
write
,monitor
, andmanage_follow_index
index privileges for the follower index. You must haveread
andmonitor
index privileges for the leader index. You must also havemanage_ccr
cluster privileges on the cluster that contains the follower index. For more information, see Security privileges.
Description
editThis API creates a new follower index that is configured to follow the referenced leader index. When this API returns, the follower index exists, and cross-cluster replication starts replicating operations from the leader index to the follower index.
Path parameters
edit-
<follower_index>
- (Required, string) The name of the follower index.
Query parameters
edit-
wait_for_active_shards
- (Optional, integer) Specifies the number of shards to wait on being active before responding. This defaults to waiting on none of the shards to be active. A shard must be restored from the leader index being active. Restoring a follower shard requires transferring all the remote Lucene segment files to the follower index.
Request body
edit-
leader_index
- (Required, string) The name of the index in the leader cluster to follow.
-
remote_cluster
- (Required, string) The remote cluster containing the leader index.
-
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
editThe 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
editThis example creates a follower index named follower_index
:
PUT /follower_index/_ccr/follow?wait_for_active_shards=1 { "remote_cluster" : "remote_cluster", "leader_index" : "leader_index", "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:
{ "follow_index_created" : true, "follow_index_shards_acked" : true, "index_following_started" : true }