AWS Elasticache Terraform module

Terraform module which creates Elasticache resources on AWS.

These types of resources are supported:

• Elasticache Replication Group
• Elasticache Subnet Group
• Elasticache Parameter Group

Root module calls these modules which can also be used separately to create independent resources:

• elasticache_replication_group - creates Elasticache replication group
• elasticache_subnet_group - creates Elasticache subnet group
• elasticache_parameter_group - createsElasticache parameter group

Usage

module "elasticache-redis" {
  source = "github.com/oded-dd/terraform-aws-elasticache"

  identifier = "prod-redis"
  number_cache_clusters = 2

  engine = "redis"
  engine_version = "4.0.10"
  port = 6379

  node_type = "cache.m4.xlarge"

  automatic_failover_enabled = true

  # Elasticache parameter group
  family      = "redis4.0"

  # Elasticache subnet group
  subnet_ids = ["${data.aws_subnet_ids.prod.ids}"]

  # Elasticache security group
  security_group_ids = ["${module.redis_security_group.this_security_group_id}"]

  tags = {
    Role        = "redis"
    Environment = "prod"
  }
}

Conditional creation

There is also a way to specify an existing Elasticache subnet group and parameter group name instead of creating new resources like this:

# This Elasticache instance will be created using existing subnet and default parameter group
module "elasticache-redis" {
  source = "github.com/oded-dd/terraform-aws-elasticache"

  identifier = "test-redis"
  number_cache_clusters = 1

  engine = "redis"
  engine_version = "4.0.10"
  port = 6379

  node_type = "cache.t2.medium"

  parameter_group_name = "default.redis4.0"
  subnet_group_name = "test-redis-subnet"

  # ... omitted
}

Notes

1. This module only tested for REDIS.
2. This module is used only for REDIS replication group with Cluster status disabled.
3. This module does not create Elasticache security group. Use terraform-aws-security-group module for this.

Inputs

Name	Description	Type	Default	Required
apply_immediately	(Optional) Specifies whether any modifications are applied immediately, or during the next maintenance window.	string	false	no
at_rest_encryption_enabled	(Optional) Whether to enable encryption at rest.	string	false	no
auth_token	(Optional) The password used to access a password protected server	string	``	no
auto_minor_version_upgrade	(Optional) Specifies whether a minor engine upgrades will be applied automatically to the underlying Cache Cluster instances during the maintenance window.	string	true	no
automatic_failover_enabled	(Optional) Specifies whether a read-only replica will be automatically promoted to read/write primary if the existing primary fails.	string	false	no
availability_zones	(Optional) A list of EC2 availability zones in which the replication group's cache clusters will be created.	list	<list>	no
create_db_instance	Whether to create this resource or not	string	true	no
engine	(Required) The name of the cache engine to be used for the clusters in this replication group.	string	-	yes
engine_version	(Required) The version number of the cache engine to be used for the cache clusters in this replication group.	string	-	yes
family	(Optional) The family of the ElastiCache parameter group	string	``	no
identifier	(Required) The identifier of the resource	string	-	yes
maintenance_window	(Optional) Specifies the weekly time range for when maintenance on the cache cluster is performed. The format is ddd:hh24:mi-ddd:hh24:mi (24H Clock UTC).	string	``	no
node_type	(Required) The compute and memory capacity of the nodes in the node group.	string	-	yes
notification_topic_arn	(Optional) An Amazon Resource Name (ARN) of an SNS topic to send ElastiCache notifications to.	string	``	no
number_cache_clusters	(Required) The number of cache clusters (primary and replicas) this replication group will have	string	-	yes
parameter_group_name	(Optional) 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	string	``	no
parameters	(Optional) A list of ElastiCache parameters to apply	string	<list>	no
port	(Required) The port number on which each of the cache nodes will accept connections.	string	-	yes
security_group_ids	(Optional) 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	list	<list>	no
snapshot_arns	(Optional) A single-element string list containing an Amazon Resource Name (ARN) of a Redis RDB snapshot file stored in Amazon S3.	list	<list>	no
snapshot_name	(Optional) The name of a snapshot from which to restore data into the new node group.	string	``	no
snapshot_retention_limit	(Optional) The number of days for which ElastiCache will retain automatic cache cluster snapshots before deleting them.	string	0	no
snapshot_window	(Optional) The daily time range (in UTC) during which ElastiCache will begin taking a daily snapshot of your cache cluster.	string	``	no
subnet_group_name	(Optional) The name of the cache subnet group to be used for the replication group	string	``	no
subnet_ids	(Required) List of VPC Subnet IDs for the cache subnet group	list	<list>	no
tags	(Optional) A mapping of tags to assign to the resource	map	<map>	no
transit_encryption_enabled	(Optional) Whether to enable encryption in transit.	string	false	no

Outputs

Name	Description
this_elasticache_parameter_group_id	The ElastiCache parameter group name
this_elasticache_replication_group_id	The ID of the ElastiCache Replication Group
this_elasticache_replication_group_primary_endpoint_address	(Redis only) The address of the endpoint for the primary node in the replication group, if the cluster mode is disabled
this_elasticache_subnet_group_name	The name for the cache subnet group

Authors

Module managed by Oded David.

License

Apache 2 Licensed. See LICENSE for full details.