Merges two adjacent shards in a Kinesis data stream and combines them into a single shard to reduce the stream’s capacity to ingest and transport data. This API is only supported for the data streams with the provisioned capacity mode. Two shards are considered adjacent if the union of the hash key ranges for the two shards form a contiguous set with no gaps. For example, if you have two shards, one with a hash key range of 276…381 and the other with a hash key range of 382…454, then you could merge these two shards into a single shard that would have a hash key range of 276…454. After the merge, the single child shard receives data for all hash key values covered by the two parent shards.
When invoking this API, it is recommended you use the
StreamARNinput parameter rather than the
MergeShards is called when there is a need to reduce the overall capacity of a stream because of excess capacity that is not being used. You must specify the shard to be merged and the adjacent shard for a stream. For more information about merging shards, see Merge Two Shards in the Amazon Kinesis Data Streams Developer Guide .
If the stream is in the
ACTIVE state, you can call
MergeShards . If a stream is in the
UPDATING , or
MergeShards returns a
ResourceInUseException . If the specified stream does not exist,
MergeShards returns a
You can use DescribeStreamSummary to check the state of the stream, which is returned in
MergeShardsis an asynchronous operation. Upon receiving a
MergeShardsrequest, Amazon Kinesis Data Streams immediately returns a response and sets the
UPDATING. After the operation is completed, Kinesis Data Streams sets the
ACTIVE. Read and write operations continue to work while the stream is in the
You use DescribeStreamSummary and the ListShards APIs to determine the shard IDs that are specified in the
If you try to operate on too many streams in parallel using CreateStream , DeleteStream ,
MergeShards , or SplitShard , you receive a
MergeShardshas a limit of five transactions per second per account.
See also: AWS API Documentation
merge-shards [--stream-name <value>] --shard-to-merge <value> --adjacent-shard-to-merge <value> [--stream-arn <value>] [--cli-input-json | --cli-input-yaml] [--generate-cli-skeleton <value>] [--debug] [--endpoint-url <value>] [--no-verify-ssl] [--no-paginate] [--output <value>] [--query <value>] [--profile <value>] [--region <value>] [--version <value>] [--color <value>] [--no-sign-request] [--ca-bundle <value>] [--cli-read-timeout <value>] [--cli-connect-timeout <value>] [--cli-binary-format <value>] [--no-cli-pager] [--cli-auto-prompt] [--no-cli-auto-prompt]
The name of the stream for the merge.
The shard ID of the shard to combine with the adjacent shard for the merge.
The shard ID of the adjacent shard for the merge.
The ARN of the stream.
Reads arguments from the JSON string provided. The JSON string follows the format provided by
--generate-cli-skeleton. If other arguments are provided on the command line, those values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally. This may not be specified along with
Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value
input, prints a sample input JSON that can be used as an argument for
--cli-input-json. Similarly, if provided
yaml-input it will print a sample input YAML that can be used with
--cli-input-yaml. If provided with the value
output, it validates the command inputs and returns a sample output JSON for that command. The generated JSON skeleton is not stable between versions of the AWS CLI and there are no backwards compatibility guarantees in the JSON skeleton generated.
Turn on debug logging.
Override command’s default URL with the given URL.
By default, the AWS CLI uses SSL when communicating with AWS services. For each SSL connection, the AWS CLI will verify SSL certificates. This option overrides the default behavior of verifying SSL certificates.
Disable automatic pagination.
The formatting style for command output.
A JMESPath query to use in filtering the response data.
Use a specific profile from your credential file.
The region to use. Overrides config/env settings.
Display the version of this tool.
Turn on/off color output.
Do not sign requests. Credentials will not be loaded if this argument is provided.
The CA certificate bundle to use when verifying SSL certificates. Overrides config/env settings.
The maximum socket read time in seconds. If the value is set to 0, the socket read will be blocking and not timeout. The default value is 60 seconds.
The maximum socket connect time in seconds. If the value is set to 0, the socket connect will be blocking and not timeout. The default value is 60 seconds.
The formatting style to be used for binary blobs. The default format is base64. The base64 format expects binary blobs to be provided as a base64 encoded string. The raw-in-base64-out format preserves compatibility with AWS CLI V1 behavior and binary values must be passed literally. When providing contents from a file that map to a binary blob
fileb:// will always be treated as binary and use the file contents directly regardless of the
cli-binary-format setting. When using
file:// the file contents will need to properly formatted for the configured
Disable cli pager for output.
Automatically prompt for CLI input parameters.
Disable automatically prompt for CLI input parameters.
To use the following examples, you must have the AWS CLI installed and configured. See the Getting started guide in the AWS CLI User Guide for more information.
Unless otherwise stated, all examples have unix-like quotation rules. These examples will need to be adapted to your terminal’s quoting rules. See Using quotation marks with strings in the AWS CLI User Guide .
To merge shards
merge-shards example merges two adjacent shards with IDs of shardId-000000000000 and shardId-000000000001 in the specified data stream and combines them into a single shard.
aws kinesis merge-shards \ --stream-name samplestream \ --shard-to-merge shardId-000000000000 \ --adjacent-shard-to-merge shardId-000000000001
This command produces no output.
For more information, see Merging Two Shards in the Amazon Kinesis Data Streams Developer Guide.