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Create Replication Group

elasticache_create_replication_group R Documentation

Creates a Redis OSS (cluster mode disabled) or a Redis OSS (cluster mode enabled) replication group

Description

Creates a Redis OSS (cluster mode disabled) or a Redis OSS (cluster mode enabled) replication group.

This API can be used to create a standalone regional replication group or a secondary replication group associated with a Global datastore.

A Redis OSS (cluster mode disabled) replication group is a collection of nodes, where one of the nodes is a read/write primary and the others are read-only replicas. Writes to the primary are asynchronously propagated to the replicas.

A Redis OSS cluster-mode enabled cluster is comprised of from 1 to 90 shards (API/CLI: node groups). Each shard has a primary node and up to 5 read-only replica nodes. The configuration can range from 90 shards and 0 replicas to 15 shards and 5 replicas, which is the maximum number or replicas allowed.

The node or shard limit can be increased to a maximum of 500 per cluster if the Redis OSS engine version is 5.0.6 or higher. For example, you can choose to configure a 500 node cluster that ranges between 83 shards (one primary and 5 replicas per shard) and 500 shards (single primary and no replicas). Make sure there are enough available IP addresses to accommodate the increase. Common pitfalls include the subnets in the subnet group have too small a CIDR range or the subnets are shared and heavily used by other clusters. For more information, see Creating a Subnet Group. For versions below 5.0.6, the limit is 250 per cluster.

To request a limit increase, see Amazon Service Limits and choose the limit type Nodes per cluster per instance type.

When a Redis OSS (cluster mode disabled) replication group has been successfully created, you can add one or more read replicas to it, up to a total of 5 read replicas. If you need to increase or decrease the number of node groups (console: shards), you can use ElastiCache (Redis OSS) scaling. For more information, see Scaling ElastiCache (Redis OSS) Clusters in the ElastiCache User Guide.

This operation is valid for Redis OSS only.

Usage

elasticache_create_replication_group(ReplicationGroupId,
  ReplicationGroupDescription, GlobalReplicationGroupId, PrimaryClusterId,
  AutomaticFailoverEnabled, MultiAZEnabled, NumCacheClusters,
  PreferredCacheClusterAZs, NumNodeGroups, ReplicasPerNodeGroup,
  NodeGroupConfiguration, CacheNodeType, Engine, EngineVersion,
  CacheParameterGroupName, CacheSubnetGroupName, CacheSecurityGroupNames,
  SecurityGroupIds, Tags, SnapshotArns, SnapshotName,
  PreferredMaintenanceWindow, Port, NotificationTopicArn,
  AutoMinorVersionUpgrade, SnapshotRetentionLimit, SnapshotWindow,
  AuthToken, TransitEncryptionEnabled, AtRestEncryptionEnabled, KmsKeyId,
  UserGroupIds, LogDeliveryConfigurations, DataTieringEnabled,
  NetworkType, IpDiscovery, TransitEncryptionMode, ClusterMode,
  ServerlessCacheSnapshotName)

Arguments

ReplicationGroupId

[required] The replication group identifier. This parameter is stored as a lowercase string.

Constraints:

  • A name must contain from 1 to 40 alphanumeric characters or hyphens.

  • The first character must be a letter.

  • A name cannot end with a hyphen or contain two consecutive hyphens.

ReplicationGroupDescription

[required] A user-created description for the replication group.

GlobalReplicationGroupId

The name of the Global datastore

PrimaryClusterId

The identifier of the cluster that serves as the primary for this replication group. This cluster must already exist and have a status of available.

This parameter is not required if NumCacheClusters, NumNodeGroups, or ReplicasPerNodeGroup is specified.

AutomaticFailoverEnabled

Specifies whether a read-only replica is automatically promoted to read/write primary if the existing primary fails.

AutomaticFailoverEnabled must be enabled for Redis OSS (cluster mode enabled) replication groups.

Default: false

MultiAZEnabled

A flag indicating if you have Multi-AZ enabled to enhance fault tolerance. For more information, see Minimizing Downtime: Multi-AZ.

NumCacheClusters

The number of clusters this replication group initially has.

This parameter is not used if there is more than one node group (shard). You should use ReplicasPerNodeGroup instead.

If AutomaticFailoverEnabled is true, the value of this parameter must be at least 2. If AutomaticFailoverEnabled is false you can omit this parameter (it will default to 1), or you can explicitly set it to a value between 2 and 6.

The maximum permitted value for NumCacheClusters is 6 (1 primary plus 5 replicas).

PreferredCacheClusterAZs

A list of EC2 Availability Zones in which the replication group's clusters are created. The order of the Availability Zones in the list is the order in which clusters are allocated. The primary cluster is created in the first AZ in the list.

This parameter is not used if there is more than one node group (shard). You should use NodeGroupConfiguration instead.

If you are creating your replication group in an Amazon VPC (recommended), you can only locate clusters in Availability Zones associated with the subnets in the selected subnet group.

The number of Availability Zones listed must equal the value of NumCacheClusters.

Default: system chosen Availability Zones.

NumNodeGroups

An optional parameter that specifies the number of node groups (shards) for this Redis OSS (cluster mode enabled) replication group. For Redis OSS (cluster mode disabled) either omit this parameter or set it to 1.

Default: 1

ReplicasPerNodeGroup

An optional parameter that specifies the number of replica nodes in each node group (shard). Valid values are 0 to 5.

NodeGroupConfiguration

A list of node group (shard) configuration options. Each node group (shard) configuration has the following members: PrimaryAvailabilityZone, ReplicaAvailabilityZones, ReplicaCount, and Slots.

If you're creating a Redis OSS (cluster mode disabled) or a Redis OSS (cluster mode enabled) replication group, you can use this parameter to individually configure each node group (shard), or you can omit this parameter. However, it is required when seeding a Redis OSS (cluster mode enabled) cluster from a S3 rdb file. You must configure each node group (shard) using this parameter because you must specify the slots for each node group.

CacheNodeType

The compute and memory capacity of the nodes in the node group (shard).

The following node types are supported by ElastiCache. Generally speaking, the current generation types provide more memory and computational power at lower cost when compared to their equivalent previous generation counterparts.

  • General purpose:

    • Current generation:

      M7g node types: cache.m7g.large, cache.m7g.xlarge, cache.m7g.2xlarge, cache.m7g.4xlarge, cache.m7g.8xlarge, cache.m7g.12xlarge, cache.m7g.16xlarge

      For region availability, see Supported Node Types

      M6g node types (available only for Redis OSS engine version 5.0.6 onward and for Memcached engine version 1.5.16 onward): cache.m6g.large, cache.m6g.xlarge, cache.m6g.2xlarge, cache.m6g.4xlarge, cache.m6g.8xlarge, cache.m6g.12xlarge, cache.m6g.16xlarge

      M5 node types: cache.m5.large, cache.m5.xlarge, cache.m5.2xlarge, cache.m5.4xlarge, cache.m5.12xlarge, cache.m5.24xlarge

      M4 node types: cache.m4.large, cache.m4.xlarge, cache.m4.2xlarge, cache.m4.4xlarge, cache.m4.10xlarge

      T4g node types (available only for Redis OSS engine version 5.0.6 onward and Memcached engine version 1.5.16 onward): cache.t4g.micro, cache.t4g.small, cache.t4g.medium

      T3 node types: cache.t3.micro, cache.t3.small, cache.t3.medium

      T2 node types: cache.t2.micro, cache.t2.small, cache.t2.medium

    • Previous generation: (not recommended. Existing clusters are still supported but creation of new clusters is not supported for these types.)

      T1 node types: cache.t1.micro

      M1 node types: cache.m1.small, cache.m1.medium, cache.m1.large, cache.m1.xlarge

      M3 node types: cache.m3.medium, cache.m3.large, cache.m3.xlarge, cache.m3.2xlarge

  • Compute optimized:

    • Previous generation: (not recommended. Existing clusters are still supported but creation of new clusters is not supported for these types.)

      C1 node types: cache.c1.xlarge

  • Memory optimized:

    • Current generation:

      R7g node types: cache.r7g.large, cache.r7g.xlarge, cache.r7g.2xlarge, cache.r7g.4xlarge, cache.r7g.8xlarge, cache.r7g.12xlarge, cache.r7g.16xlarge

      For region availability, see Supported Node Types

      R6g node types (available only for Redis OSS engine version 5.0.6 onward and for Memcached engine version 1.5.16 onward): cache.r6g.large, cache.r6g.xlarge, cache.r6g.2xlarge, cache.r6g.4xlarge, cache.r6g.8xlarge, cache.r6g.12xlarge, cache.r6g.16xlarge

      R5 node types: cache.r5.large, cache.r5.xlarge, cache.r5.2xlarge, cache.r5.4xlarge, cache.r5.12xlarge, cache.r5.24xlarge

      R4 node types: cache.r4.large, cache.r4.xlarge, cache.r4.2xlarge, cache.r4.4xlarge, cache.r4.8xlarge, cache.r4.16xlarge

    • Previous generation: (not recommended. Existing clusters are still supported but creation of new clusters is not supported for these types.)

      M2 node types: cache.m2.xlarge, cache.m2.2xlarge, cache.m2.4xlarge

      R3 node types: cache.r3.large, cache.r3.xlarge, cache.r3.2xlarge, cache.r3.4xlarge, cache.r3.8xlarge

Additional node type info

  • All current generation instance types are created in Amazon VPC by default.

  • Redis OSS append-only files (AOF) are not supported for T1 or T2 instances.

  • Redis OSS Multi-AZ with automatic failover is not supported on T1 instances.

  • Redis OSS configuration variables appendonly and appendfsync are not supported on Redis OSS version 2.8.22 and later.

Engine

The name of the cache engine to be used for the clusters in this replication group. The value must be set to Redis.

EngineVersion

The version number of the cache engine to be used for the clusters in this replication group. To view the supported cache engine versions, use the describe_cache_engine_versions operation.

Important: You can upgrade to a newer engine version (see Selecting a Cache Engine and Version) in the ElastiCache User Guide, but you cannot downgrade to an earlier engine version. If you want to use an earlier engine version, you must delete the existing cluster or replication group and create it anew with the earlier engine version.

CacheParameterGroupName

The name of the parameter group to associate with this replication group. If this argument is omitted, the default cache parameter group for the specified engine is used.

If you are running Redis OSS version 3.2.4 or later, only one node group (shard), and want to use a default parameter group, we recommend that you specify the parameter group by name.

  • To create a Redis OSS (cluster mode disabled) replication group, use CacheParameterGroupName=default.redis3.2.

  • To create a Redis OSS (cluster mode enabled) replication group, use CacheParameterGroupName=default.redis3.2.cluster.on.

CacheSubnetGroupName

The name of the cache subnet group to be used for the replication group.

If you're going to launch your cluster in an Amazon VPC, you need to create a subnet group before you start creating a cluster. For more information, see Subnets and Subnet Groups.

CacheSecurityGroupNames

A list of cache security group names to associate with this replication group.

SecurityGroupIds

One or more Amazon VPC security groups associated with this replication group.

Use this parameter only when you are creating a replication group in an Amazon Virtual Private Cloud (Amazon VPC).

Tags

A list of tags to be added to this resource. Tags are comma-separated key,value pairs (e.g. Key=myKey, Value=myKeyValue. You can include multiple tags as shown following: Key=myKey, Value=myKeyValue Key=mySecondKey, Value=mySecondKeyValue. Tags on replication groups will be replicated to all nodes.

SnapshotArns

A list of Amazon Resource Names (ARN) that uniquely identify the Redis OSS RDB snapshot files stored in Amazon S3. The snapshot files are used to populate the new replication group. The Amazon S3 object name in the ARN cannot contain any commas. The new replication group will have the number of node groups (console: shards) specified by the parameter NumNodeGroups or the number of node groups configured by NodeGroupConfiguration regardless of the number of ARNs specified here.

Example of an Amazon S3 ARN: arn:aws:s3:::my_bucket/snapshot1.rdb

SnapshotName

The name of a snapshot from which to restore data into the new replication group. The snapshot status changes to restoring while the new replication group is being created.

PreferredMaintenanceWindow

Specifies the weekly time range during which maintenance on the cluster is performed. It is specified as a range in the format ddd:hh24:mi-ddd:hh24:mi (24H Clock UTC). The minimum maintenance window is a 60 minute period.

Valid values for ddd are:

  • sun

  • mon

  • tue

  • wed

  • thu

  • fri

  • sat

Example: sun:23:00-mon:01:30

Port

The port number on which each member of the replication group accepts connections.

NotificationTopicArn

The Amazon Resource Name (ARN) of the Amazon Simple Notification Service (SNS) topic to which notifications are sent.

The Amazon SNS topic owner must be the same as the cluster owner.

AutoMinorVersionUpgrade

If you are running Redis OSS engine version 6.0 or later, set this parameter to yes if you want to opt-in to the next auto minor version upgrade campaign. This parameter is disabled for previous versions.

SnapshotRetentionLimit

The number of days for which ElastiCache retains automatic snapshots before deleting them. For example, if you set SnapshotRetentionLimit to 5, a snapshot that was taken today is retained for 5 days before being deleted.

Default: 0 (i.e., automatic backups are disabled for this cluster).

SnapshotWindow

The daily time range (in UTC) during which ElastiCache begins taking a daily snapshot of your node group (shard).

Example: 05:00-09:00

If you do not specify this parameter, ElastiCache automatically chooses an appropriate time range.

AuthToken

Reserved parameter. The password used to access a password protected server.

AuthToken can be specified only on replication groups where TransitEncryptionEnabled is true.

For HIPAA compliance, you must specify TransitEncryptionEnabled as true, an AuthToken, and a CacheSubnetGroup.

Password constraints:

  • Must be only printable ASCII characters.

  • Must be at least 16 characters and no more than 128 characters in length.

  • The only permitted printable special characters are !, &, #, $, ^, \<, \>, and -. Other printable special characters cannot be used in the AUTH token.

For more information, see AUTH password at http://redis.io/commands/AUTH.

TransitEncryptionEnabled

A flag that enables in-transit encryption when set to true.

This parameter is valid only if the Engine parameter is redis, the EngineVersion parameter is ⁠3.2.6⁠, ⁠4.x⁠ or later, and the cluster is being created in an Amazon VPC.

If you enable in-transit encryption, you must also specify a value for CacheSubnetGroup.

Required: Only available when creating a replication group in an Amazon VPC using Redis OSS version ⁠3.2.6⁠, ⁠4.x⁠ or later.

Default: false

For HIPAA compliance, you must specify TransitEncryptionEnabled as true, an AuthToken, and a CacheSubnetGroup.

AtRestEncryptionEnabled

A flag that enables encryption at rest when set to true.

You cannot modify the value of AtRestEncryptionEnabled after the replication group is created. To enable encryption at rest on a replication group you must set AtRestEncryptionEnabled to true when you create the replication group.

Required: Only available when creating a replication group in an Amazon VPC using Redis OSS version ⁠3.2.6⁠, ⁠4.x⁠ or later.

Default: false

KmsKeyId

The ID of the KMS key used to encrypt the disk in the cluster.

UserGroupIds

The user group to associate with the replication group.

LogDeliveryConfigurations

Specifies the destination, format and type of the logs.

DataTieringEnabled

Enables data tiering. Data tiering is only supported for replication groups using the r6gd node type. This parameter must be set to true when using r6gd nodes. For more information, see Data tiering.

NetworkType

Must be either ipv4 | ipv6 | dual_stack. IPv6 is supported for workloads using Redis OSS engine version 6.2 onward or Memcached engine version 1.6.6 on all instances built on the Nitro system.

IpDiscovery

The network type you choose when creating a replication group, either ipv4 | ipv6. IPv6 is supported for workloads using Redis OSS engine version 6.2 onward or Memcached engine version 1.6.6 on all instances built on the Nitro system.

TransitEncryptionMode

A setting that allows you to migrate your clients to use in-transit encryption, with no downtime.

When setting TransitEncryptionEnabled to true, you can set your TransitEncryptionMode to preferred in the same request, to allow both encrypted and unencrypted connections at the same time. Once you migrate all your Redis OSS clients to use encrypted connections you can modify the value to required to allow encrypted connections only.

Setting TransitEncryptionMode to required is a two-step process that requires you to first set the TransitEncryptionMode to preferred, after that you can set TransitEncryptionMode to required.

This process will not trigger the replacement of the replication group.

ClusterMode

Enabled or Disabled. To modify cluster mode from Disabled to Enabled, you must first set the cluster mode to Compatible. Compatible mode allows your Redis OSS clients to connect using both cluster mode enabled and cluster mode disabled. After you migrate all Redis OSS clients to use cluster mode enabled, you can then complete cluster mode configuration and set the cluster mode to Enabled.

ServerlessCacheSnapshotName

The name of the snapshot used to create a replication group. Available for Redis OSS only.

Value

A list with the following syntax:

list(
  ReplicationGroup = list(
    ReplicationGroupId = "string",
    Description = "string",
    GlobalReplicationGroupInfo = list(
      GlobalReplicationGroupId = "string",
      GlobalReplicationGroupMemberRole = "string"
    ),
    Status = "string",
    PendingModifiedValues = list(
      PrimaryClusterId = "string",
      AutomaticFailoverStatus = "enabled"|"disabled",
      Resharding = list(
        SlotMigration = list(
          ProgressPercentage = 123.0
        )
      ),
      AuthTokenStatus = "SETTING"|"ROTATING",
      UserGroups = list(
        UserGroupIdsToAdd = list(
          "string"
        ),
        UserGroupIdsToRemove = list(
          "string"
        )
      ),
      LogDeliveryConfigurations = list(
        list(
          LogType = "slow-log"|"engine-log",
          DestinationType = "cloudwatch-logs"|"kinesis-firehose",
          DestinationDetails = list(
            CloudWatchLogsDetails = list(
              LogGroup = "string"
            ),
            KinesisFirehoseDetails = list(
              DeliveryStream = "string"
            )
          ),
          LogFormat = "text"|"json"
        )
      ),
      TransitEncryptionEnabled = TRUE|FALSE,
      TransitEncryptionMode = "preferred"|"required",
      ClusterMode = "enabled"|"disabled"|"compatible"
    ),
    MemberClusters = list(
      "string"
    ),
    NodeGroups = list(
      list(
        NodeGroupId = "string",
        Status = "string",
        PrimaryEndpoint = list(
          Address = "string",
          Port = 123
        ),
        ReaderEndpoint = list(
          Address = "string",
          Port = 123
        ),
        Slots = "string",
        NodeGroupMembers = list(
          list(
            CacheClusterId = "string",
            CacheNodeId = "string",
            ReadEndpoint = list(
              Address = "string",
              Port = 123
            ),
            PreferredAvailabilityZone = "string",
            PreferredOutpostArn = "string",
            CurrentRole = "string"
          )
        )
      )
    ),
    SnapshottingClusterId = "string",
    AutomaticFailover = "enabled"|"disabled"|"enabling"|"disabling",
    MultiAZ = "enabled"|"disabled",
    ConfigurationEndpoint = list(
      Address = "string",
      Port = 123
    ),
    SnapshotRetentionLimit = 123,
    SnapshotWindow = "string",
    ClusterEnabled = TRUE|FALSE,
    CacheNodeType = "string",
    AuthTokenEnabled = TRUE|FALSE,
    AuthTokenLastModifiedDate = as.POSIXct(
      "2015-01-01"
    ),
    TransitEncryptionEnabled = TRUE|FALSE,
    AtRestEncryptionEnabled = TRUE|FALSE,
    MemberClustersOutpostArns = list(
      "string"
    ),
    KmsKeyId = "string",
    ARN = "string",
    UserGroupIds = list(
      "string"
    ),
    LogDeliveryConfigurations = list(
      list(
        LogType = "slow-log"|"engine-log",
        DestinationType = "cloudwatch-logs"|"kinesis-firehose",
        DestinationDetails = list(
          CloudWatchLogsDetails = list(
            LogGroup = "string"
          ),
          KinesisFirehoseDetails = list(
            DeliveryStream = "string"
          )
        ),
        LogFormat = "text"|"json",
        Status = "active"|"enabling"|"modifying"|"disabling"|"error",
        Message = "string"
      )
    ),
    ReplicationGroupCreateTime = as.POSIXct(
      "2015-01-01"
    ),
    DataTiering = "enabled"|"disabled",
    AutoMinorVersionUpgrade = TRUE|FALSE,
    NetworkType = "ipv4"|"ipv6"|"dual_stack",
    IpDiscovery = "ipv4"|"ipv6",
    TransitEncryptionMode = "preferred"|"required",
    ClusterMode = "enabled"|"disabled"|"compatible"
  )
)

Request syntax

svc$create_replication_group(
  ReplicationGroupId = "string",
  ReplicationGroupDescription = "string",
  GlobalReplicationGroupId = "string",
  PrimaryClusterId = "string",
  AutomaticFailoverEnabled = TRUE|FALSE,
  MultiAZEnabled = TRUE|FALSE,
  NumCacheClusters = 123,
  PreferredCacheClusterAZs = list(
    "string"
  ),
  NumNodeGroups = 123,
  ReplicasPerNodeGroup = 123,
  NodeGroupConfiguration = list(
    list(
      NodeGroupId = "string",
      Slots = "string",
      ReplicaCount = 123,
      PrimaryAvailabilityZone = "string",
      ReplicaAvailabilityZones = list(
        "string"
      ),
      PrimaryOutpostArn = "string",
      ReplicaOutpostArns = list(
        "string"
      )
    )
  ),
  CacheNodeType = "string",
  Engine = "string",
  EngineVersion = "string",
  CacheParameterGroupName = "string",
  CacheSubnetGroupName = "string",
  CacheSecurityGroupNames = list(
    "string"
  ),
  SecurityGroupIds = list(
    "string"
  ),
  Tags = list(
    list(
      Key = "string",
      Value = "string"
    )
  ),
  SnapshotArns = list(
    "string"
  ),
  SnapshotName = "string",
  PreferredMaintenanceWindow = "string",
  Port = 123,
  NotificationTopicArn = "string",
  AutoMinorVersionUpgrade = TRUE|FALSE,
  SnapshotRetentionLimit = 123,
  SnapshotWindow = "string",
  AuthToken = "string",
  TransitEncryptionEnabled = TRUE|FALSE,
  AtRestEncryptionEnabled = TRUE|FALSE,
  KmsKeyId = "string",
  UserGroupIds = list(
    "string"
  ),
  LogDeliveryConfigurations = list(
    list(
      LogType = "slow-log"|"engine-log",
      DestinationType = "cloudwatch-logs"|"kinesis-firehose",
      DestinationDetails = list(
        CloudWatchLogsDetails = list(
          LogGroup = "string"
        ),
        KinesisFirehoseDetails = list(
          DeliveryStream = "string"
        )
      ),
      LogFormat = "text"|"json",
      Enabled = TRUE|FALSE
    )
  ),
  DataTieringEnabled = TRUE|FALSE,
  NetworkType = "ipv4"|"ipv6"|"dual_stack",
  IpDiscovery = "ipv4"|"ipv6",
  TransitEncryptionMode = "preferred"|"required",
  ClusterMode = "enabled"|"disabled"|"compatible",
  ServerlessCacheSnapshotName = "string"
)