README.md

April 15, 2026 · View on GitHub

This component provisions AWS ElastiCache Redis clusters. The engine can either be redis or valkey. For more information, see why aws supports valkey.

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In Cloud Posse's examples, we avoid pinning modules to specific versions to prevent discrepancies between the documentation and the latest released versions. However, for your own projects, we strongly advise pinning each module to the exact version you're using. This practice ensures the stability of your infrastructure. Additionally, we recommend implementing a systematic approach for updating versions to avoid unexpected changes.

Requirements

Name	Version
terraform	>= 1.0.0
aws	>= 5.73.0, < 7.0.0
utils	>= 2.0.0, < 3.0.0

Providers

No providers.

Modules

Name	Source	Version
dns_delegated	cloudposse/stack-config/yaml//modules/remote-state	2.0.0
eks	cloudposse/stack-config/yaml//modules/remote-state	2.0.0
iam_roles	../account-map/modules/iam-roles	n/a
redis_clusters	./modules/redis_cluster	n/a
this	cloudposse/label/null	0.25.0
vpc	cloudposse/stack-config/yaml//modules/remote-state	2.0.0
vpc_ingress	cloudposse/stack-config/yaml//modules/remote-state	2.0.0

Resources

No resources.

Inputs

Name	Description	Type	Default	Required
additional_security_group_rules	A list of Security Group rule objects to add to the created security group, in addition to the ones this module normally creates.	`list(any)`	`[]`	no
additional_tag_map	Additional key-value pairs to add to each map in `tags_as_list_of_maps`. Not added to `tags` or `id`. This is for some rare cases where resources want additional configuration of tags and therefore take a list of maps with tag key, value, and additional configuration.	`map(string)`	`{}`	no
alarm_actions	Alarm action list	`list(string)`	`[]`	no
alarm_cpu_threshold_percent	CPU threshold alarm level	`number`	`75`	no
alarm_memory_threshold_bytes	Ram threshold alarm level	`number`	`10000000`	no
allow_all_egress	If `true`, the created security group will allow egress on all ports and protocols to all IP address. If this is false and no egress rules are otherwise specified, then no egress will be allowed.	`bool`	`true`	no
allow_ingress_from_this_vpc	If set to `true`, allow ingress from the VPC CIDR for this account	`bool`	`true`	no
allow_ingress_from_vpc_stages	List of stages to pull VPC ingress cidr and add to security group	`list(string)`	`[]`	no
apply_immediately	Apply changes immediately	`bool`	n/a	yes
at_rest_encryption_enabled	Enable encryption at rest	`bool`	n/a	yes
attributes	ID element. Additional attributes (e.g. `workers` or `cluster`) to add to `id`, in the order they appear in the list. New attributes are appended to the end of the list. The elements of the list are joined by the `delimiter` and treated as a single ID element.	`list(string)`	`[]`	no
auth_token_enabled	Enable auth token	`bool`	`true`	no
auth_token_update_strategy	Strategy to use when updating the auth_token. Valid values are `SET`, `ROTATE`, and `DELETE`. Defaults to `ROTATE`.	`string`	`"ROTATE"`	no
auto_minor_version_upgrade	Specifies whether minor version engine upgrades will be applied automatically to the underlying Cache Cluster instances during the maintenance window. Only supported if the engine version is 6 or higher.	`bool`	`false`	no
automatic_failover_enabled	Enable automatic failover	`bool`	n/a	yes
availability_zones	Availability zone IDs	`list(string)`	`[]`	no
cloudwatch_metric_alarms_enabled	Boolean flag to enable/disable CloudWatch metrics alarms	`bool`	n/a	yes
context	Single object for setting entire context at once. See description of individual variables for details. Leave string and numeric variables as `null` to use default value. Individual variable settings (non-null) override settings in context object, except for attributes, tags, and additional_tag_map, which are merged.	`any`	{ "additional_tag_map": {}, "attributes": [], "delimiter": null, "descriptor_formats": {}, "enabled": true, "environment": null, "id_length_limit": null, "label_key_case": null, "label_order": [], "label_value_case": null, "labels_as_tags": [ "unset" ], "name": null, "namespace": null, "regex_replace_chars": null, "stage": null, "tags": {}, "tenant": null }	no
create_parameter_group	Default setting for whether a new parameter group should be created for all Redis clusters. Set to false to use an existing parameter group. Can be overridden per cluster in redis_clusters.	`bool`	`true`	no
data_tiering_enabled	Enables data tiering. Data tiering is only supported for replication groups using the r6gd node type.	`bool`	`false`	no
delimiter	Delimiter to be used between ID elements. Defaults to `-` (hyphen). Set to `""` to use no delimiter at all.	`string`	`null`	no
description	Default description for all Redis replication groups. Can be overridden per cluster in redis_clusters.	`string`	`null`	no
descriptor_formats	Describe additional descriptors to be output in the `descriptors` output map. Map of maps. Keys are names of descriptors. Values are maps of the form `{<br/> format = string<br/> labels = list(string)<br/>}` (Type is `any` so the map values can later be enhanced to provide additional options.) `format` is a Terraform format string to be passed to the `format()` function. `labels` is a list of labels, in order, to pass to `format()` function. Label values will be normalized before being passed to `format()` so they will be identical to how they appear in `id`. Default is `{}` (`descriptors` output will be empty).	`any`	`{}`	no
dns_delegated_component_name	The name of the Delegated DNS component	`string`	`"dns-delegated"`	no
egress_cidr_blocks	Egress CIDR blocks for the created security group. Only used when `allow_all_egress` is `false`.	`list(string)`	[ "0.0.0.0/0" ]	no
egress_cidr_blocks_rule_description	Description for the security group rule allowing egress to the CIDR blocks in `egress_cidr_blocks`. Only used when `allow_all_egress` is `false`.	`string`	`"Selectively allow outbound traffic"`	no
eks_component_names	The names of the eks components	`set(string)`	`[]`	no
eks_security_group_enabled	Use the eks default security group	`bool`	`false`	no
elasticache_subnet_group_name	Subnet group name for the ElastiCache instance	`string`	`""`	no
enabled	Set to false to prevent the module from creating any resources	`bool`	`null`	no
engine	Default cache engine for all Redis clusters. Valid values: `redis` or `valkey`. Can be overridden per cluster in redis_clusters.	`string`	`"redis"`	no
engine_version	Default engine version for all Redis clusters (e.g. `7.0`). Can be overridden per cluster in redis_clusters.	`string`	`null`	no
environment	ID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'	`string`	`null`	no
family	Redis family	`string`	n/a	yes
final_snapshot_identifier	Default name of the final snapshot to create before deleting all Redis clusters. If null, no final snapshot is created. Can be overridden per cluster in redis_clusters.	`string`	`null`	no
global_replication_group_id	The ID of the global replication group to which this replication group should belong. If this parameter is specified, the replication group is added to the specified global replication group as a secondary replication group; otherwise, the replication group is not part of any global replication group. If global_replication_group_id is set, the num_node_groups parameter cannot be set.	`string`	`null`	no
id_length_limit	Limit `id` to this many characters (minimum 6). Set to `0` for unlimited length. Set to `null` for keep the existing setting, which defaults to `0`. Does not affect `id_full`.	`number`	`null`	no
ingress_cidr_blocks	CIDR blocks for permitted ingress	`list(string)`	`[]`	no
ingress_cidr_blocks_rule_description	Description for the security group rule allowing ingress from the CIDR blocks in `ingress_cidr_blocks`.	`string`	`"Selectively allow inbound traffic"`	no
instance_type	Default instance type for all Redis clusters. Can be overridden per cluster in redis_clusters.	`string`	`null`	no
kms_key_id	The ARN of the key that you wish to use if encrypting at rest. If not supplied, uses service managed encryption. `at_rest_encryption_enabled` must be set to `true`	`string`	`null`	no
label_key_case	Controls the letter case of the `tags` keys (label names) for tags generated by this module. Does not affect keys of tags passed in via the `tags` input. Possible values: `lower`, `title`, `upper`. Default value: `title`.	`string`	`null`	no
label_order	The order in which the labels (ID elements) appear in the `id`. Defaults to ["namespace", "environment", "stage", "name", "attributes"]. You can omit any of the 6 labels ("tenant" is the 6th), but at least one must be present.	`list(string)`	`null`	no
label_value_case	Controls the letter case of ID elements (labels) as included in `id`, set as tag values, and output by this module individually. Does not affect values of tags passed in via the `tags` input. Possible values: `lower`, `title`, `upper` and `none` (no transformation). Set this to `title` and set `delimiter` to `""` to yield Pascal Case IDs. Default value: `lower`.	`string`	`null`	no
labels_as_tags	Set of labels (ID elements) to include as tags in the `tags` output. Default is to include all labels. Tags with empty values will not be included in the `tags` output. Set to `[]` to suppress all generated tags. Notes: The value of the `name` tag, if included, will be the `id`, not the `name`. Unlike other `null-label` inputs, the initial setting of `labels_as_tags` cannot be changed in later chained modules. Attempts to change it will be silently ignored.	`set(string)`	[ "default" ]	no
log_delivery_configuration	The log_delivery_configuration block allows the streaming of Redis SLOWLOG or Redis Engine Log to CloudWatch Logs or Kinesis Data Firehose. Max of 2 blocks.	`list(map(any))`	`[]`	no
maintenance_window	Maintenance window. Format: ddd:hh:mm-ddd:hh:mm (UTC). Defaults to null (AWS chooses the window).	`string`	`null`	no
multi_az_enabled	Multi AZ (Automatic Failover must also be enabled. If Cluster Mode is enabled, Multi AZ is on by default, and this setting is ignored)	`bool`	`false`	no
name	ID element. Usually the component or solution name, e.g. 'app' or 'jenkins'. This is the only ID element not also included as a `tag`. The "name" tag is set to the full `id` string. There is no tag with the value of the `name` input.	`string`	`null`	no
namespace	ID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique	`string`	`null`	no
network_type	The network type of the cluster. Valid values: ipv4, ipv6, dual_stack.	`string`	`"ipv4"`	no
notification_topic_arn	Notification topic arn	`string`	`""`	no
num_replicas	Default number of replicas in the replica set for all Redis clusters. Can be overridden per cluster in redis_clusters.	`number`	`1`	no
num_shards	Default number of shards (node groups) for Redis clusters. Value > 0 enables cluster mode. Can be overridden per cluster in redis_clusters.	`number`	`0`	no
ok_actions	The list of actions to execute when this alarm transitions into an OK state from any other state. Each action is specified as an Amazon Resource Number (ARN)	`list(string)`	`[]`	no
parameter_group_description	Managed by Terraform	`string`	`null`	no
parameter_group_name	Default override parameter group name for all Redis clusters. Can be overridden per cluster in redis_clusters.	`string`	`null`	no
parameters	Default list of Redis parameters to configure for all clusters. Can be overridden per cluster in redis_clusters.	list(object({ name = string value = string }))	`[]`	no
port	Port number	`number`	n/a	yes
redis_clusters	Redis cluster configuration	`map(any)`	n/a	yes
regex_replace_chars	Terraform regular expression (regex) string. Characters matching the regex will be removed from the ID elements. If not set, `"/[^a-zA-Z0-9-]/"` is used to remove all characters other than hyphens, letters and digits.	`string`	`null`	no
region	AWS region	`string`	n/a	yes
replicas_per_shard	Default number of replica nodes per shard for Redis clusters. Valid values are 0 to 5. Can be overridden per cluster in redis_clusters.	`number`	`0`	no
replication_group_id	Default replication group ID for all Redis clusters. Must be 1-20 alphanumeric characters or hyphens, start with a letter, and not end with or contain consecutive hyphens. Can be overridden per cluster in redis_clusters.	`string`	`""`	no
serverless_cache_usage_limits	The usage limits for the serverless cache. Expected keys are `data_storage` (with `maximum`, `minimum`, `unit`) and `ecpu_per_second` (with `maximum`, `minimum`).	`map(any)`	`{}`	no
serverless_enabled	Flag to enable/disable creation of a serverless redis cluster	`bool`	`false`	no
serverless_major_engine_version	The major version of the engine to use for the serverless cluster	`string`	`"7"`	no
serverless_snapshot_arns_to_restore	The list of ARN(s) of the snapshot that the new serverless cache will be created from. Available for Redis only.	`list(string)`	`[]`	no
serverless_snapshot_time	The daily time (in UTC, format HH:MM) that snapshots will be created from the serverless cache.	`string`	`"06:00"`	no
serverless_user_group_id	User Group ID to associate with the serverless replication group	`string`	`null`	no
snapshot_arns	Default list of ARNs of Redis RDB snapshot files in S3 to restore into all new clusters. Can be overridden per cluster in redis_clusters.	`list(string)`	`[]`	no
snapshot_name	Default name of a snapshot to restore into all new Redis clusters. Changing this forces a new resource. Can be overridden per cluster in redis_clusters.	`string`	`null`	no
snapshot_retention_limit	The number of days for which ElastiCache will retain automatic cache cluster snapshots before deleting them.	`number`	`0`	no
snapshot_window	The daily time range (in UTC) during which ElastiCache begins taking a daily snapshot. Format: hh:mm-hh:mm. Defaults to null (AWS chooses the window). Has no effect when snapshot_retention_limit is 0.	`string`	`null`	no
stage	ID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'	`string`	`null`	no
tags	Additional tags (e.g. `{'BusinessUnit': 'XYZ'}`). Neither the tag keys nor the tag values will be modified by this module.	`map(string)`	`{}`	no
tenant	ID element _(Rarely used, not included by default)_. A customer identifier, indicating who this instance of a resource is for	`string`	`null`	no
transit_encryption_enabled	Enable TLS	`bool`	n/a	yes
transit_encryption_mode	Transit encryption mode. Valid values are 'preferred' and 'required'	`string`	`null`	no
user_group_ids	User Group ID to associate with the replication group	`list(string)`	`null`	no
vpc_component_name	The name of a VPC component	`string`	`"vpc"`	no
vpc_ingress_component_name	The name of a Ingress VPC component	`string`	`"vpc"`	no

Outputs

Name	Description
redis_clusters	Redis cluster objects
security_group_id	The security group ID of the ElastiCache Redis cluster
transit_encryption_mode	TLS in-transit encryption mode for Redis cluster

Check out these related projects.

Cloud Posse Terraform Modules - Our collection of reusable Terraform modules used by our reference architectures.
Atmos - Atmos is like docker-compose but for your infrastructure

References

For additional context, refer to some of these links.

cloudposse-terraform-components - Cloud Posse's upstream component

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Preamble to the Apache License, Version 2.0

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