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Module: elasticache-memcached

Terraform module to provision an ElastiCache Memcached Cluster

Usage​

For a complete example, see examples/complete.

For automated tests of the complete example using bats and Terratest (which tests and deploys the example on AWS), see test.

  provider "aws" {
    region = var.region
  }

  module "this" {
    source  = "cloudposse/label/null"
    # Cloud Posse recommends pinning every module to a specific version
    # version = "x.x.x"
    namespace  = var.namespace
    stage      = var.stage
    name       = var.name
  }

  module "vpc" {
    source = "cloudposse/vpc/aws"
    # Cloud Posse recommends pinning every module to a specific version
    # version = "x.x.x"

    cidr_block = "172.16.0.0/16"

    context = module.this.context
  }

  module "subnets" {
    source = "cloudposse/dynamic-subnets/aws"
    # Cloud Posse recommends pinning every module to a specific version
    # version = "x.x.x"

    availability_zones   = var.availability_zones
    vpc_id               = module.vpc.vpc_id
    igw_id               = module.vpc.igw_id
    cidr_block           = module.vpc.vpc_cidr_block
    nat_gateway_enabled  = true
    nat_instance_enabled = false

    context = module.this.context
  }

  module "memcached" {
    source = "cloudposse/elasticache-memcached/aws"
    # Cloud Posse recommends pinning every module to a specific version
    # version = "x.x.x"

    availability_zones      = var.availability_zones
    vpc_id                  = module.vpc.vpc_id
    allowed_security_groups = [module.vpc.vpc_default_security_group_id]
    subnets                 = module.subnets.private_subnet_ids
    cluster_size            = var.cluster_size
    instance_type           = var.instance_type
    engine_version          = var.engine_version
    apply_immediately       = true
    zone_id                 = var.zone_id

    elasticache_parameter_group_family = var.elasticache_parameter_group_family

    context = module.this.context
  }

Examples​

Review the complete example to see how to use this module.

Variables​

Required Variables​

Optional Variables​

additional_security_group_rules (list(any)) optional

A list of Security Group rule objects to add to the created security group, in addition to the ones
this module normally creates. (To suppress the module's rules, set create_security_group to false
and supply your own security group via associated_security_group_ids.)
The keys and values of the objects are fully compatible with the aws_security_group_rule resource, except
for security_group_id which will be ignored, and the optional "key" which, if provided, must be unique and known at "plan" time.
To get more info see https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule .



Default value: [ ]

alarm_actions (list(string)) optional

Alarm actions


Default value: [ ]

alarm_cpu_threshold_percent (number) optional

CPU threshold alarm level


Default value: 75

alarm_memory_threshold_bytes (number) optional

Alarm memory threshold bytes


Default value: 10000000

allow_all_egress (bool) optional

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.



Default value: true

allowed_cidr_blocks (list(string)) optional

A list of IPv4 CIDRs to allow access to the security group created by this module.
The length of this list must be known at "plan" time.



Default value: [ ]

allowed_ipv6_cidr_blocks (list(string)) optional

A list of IPv6 CIDRs to allow access to the security group created by this module.
The length of this list must be known at "plan" time.



Default value: [ ]

allowed_ipv6_prefix_list_ids (list(string)) optional

A list of IPv6 Prefix Lists IDs to allow access to the security group created by this module.
The length of this list must be known at "plan" time.



Default value: [ ]

allowed_security_group_ids (list(string)) optional

A list of IDs of Security Groups to allow access to the security group created by this module.
The length of this list must be known at "plan" time.



Default value: [ ]

allowed_security_groups (list(string)) optional

DEPRECATED: Use allowed_security_group_ids instead.



Default value: [ ]

apply_immediately (bool) optional

Specifies whether any database modifications are applied immediately, or during the next maintenance window


Default value: true

associated_security_group_ids (list(string)) optional

A list of IDs of Security Groups to associate the created resource with, in addition to the created security group.
These security groups will not be modified and, if create_security_group is false, must have rules providing the desired access.



Default value: [ ]

availability_zone (string) optional

The Availability Zone of the cluster. az_mode must be set to single-az when used.


Default value: ""

availability_zones (list(string)) optional

List of Availability Zones for the cluster. az_mode must be set to cross-az when used.


Default value: [ ]

az_mode (string) optional

Enable or disable multiple AZs, eg: single-az or cross-az


Default value: "single-az"

cloudwatch_metric_alarms_enabled (bool) optional

Boolean flag to enable/disable CloudWatch metrics alarms


Default value: false

cluster_size (number) optional

Cluster size


Default value: 1

create_security_group (bool) optional

Set true to create and configure a new security group. If false, associated_security_group_ids must be provided.


Default value: true

dns_subdomain (string) optional

The subdomain to use for the CNAME record. If not provided then the CNAME record will use var.name.


Default value: ""

elasticache_parameter_group_family (string) optional

ElastiCache parameter group family


Default value: "memcached1.5"

elasticache_subnet_group_name (string) optional

Subnet group name for the ElastiCache instance


Default value: ""

engine_version (string) optional

Memcached engine version. For more info, see https://docs.aws.amazon.com/AmazonElastiCache/latest/mem-ug/supported-engine-versions.html


Default value: "1.5.16"

existing_security_groups (list(string)) optional

DEPRECATED: Use associated_security_group_ids instead.
Historical description: List of existing Security Group IDs to place the cluster into.
Set use_existing_security_groups to true to enable using existing_security_groups as Security Groups for the cluster.



Default value: [ ]

instance_type (string) optional

Elastic cache instance type


Default value: "cache.t2.micro"

maintenance_window (string) optional

Maintenance window


Default value: "wed:03:00-wed:04:00"

max_item_size (number) optional

Max item size


Default value: 10485760

network_type (string) optional

The network type of the cluster. Valid values: ipv4, ipv6, dual_stack.


Default value: "ipv4"

notification_topic_arn (string) optional

Notification topic arn


Default value: ""

port (number) optional

Memcached port


Default value: 11211

security_group_create_before_destroy (bool) optional

Set true to enable Terraform create_before_destroy behavior on the created security group.
We only recommend setting this false if you are upgrading this module and need to keep
the existing security group from being replaced.
Note that changing this value will always cause the security group to be replaced.



Default value: true

security_group_create_timeout (string) optional

How long to wait for the security group to be created.


Default value: "10m"

security_group_delete_timeout (string) optional

How long to retry on DependencyViolation errors during security group deletion.



Default value: "15m"

security_group_description (string) optional

The description to assign to the created Security Group.
Warning: Changing the description causes the security group to be replaced.



Default value: "Security group for Elasticache Memcached"

security_group_name (list(string)) optional

The name to assign to the created security group. Must be unique within the VPC.
If not provided, will be derived from the null-label.context passed in.
If create_before_destroy is true, will be used as a name prefix.



Default value: [ ]

subnets (list(string)) optional

AWS subnet ids


Default value: [ ]

transit_encryption_enabled (bool) optional

Boolean flag to enable transit encryption (requires Memcached version 1.6.12+)


Default value: false

use_existing_security_groups (bool) optional

DEPRECATED: Use create_security_group instead.
Historical description: Flag to enable/disable creation of Security Group in the module.
Set to true to disable Security Group creation and provide a list of existing security Group IDs in existing_security_groups to place the cluster into.
Historical default: false



Default value: null

vpc_id (string) optional

VPC ID


Default value: ""

zone_id (string) optional

Route53 DNS Zone ID


Default value: ""

Context Variables​

The following variables are defined in the context.tf file of this module and part of the terraform-null-label pattern.

additional_tag_map (map(string)) optional

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.


Required: No

Default value: { }

attributes (list(string)) optional

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.


Required: No

Default value: [ ]

context (any) optional

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.


Required: No

Default value:

{
  "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
}
delimiter (string) optional

Delimiter to be used between ID elements.
Defaults to - (hyphen). Set to "" to use no delimiter at all.


Required: No

Default value: null

descriptor_formats (any) optional

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).


Required: No

Default value: { }

enabled (bool) optional

Set to false to prevent the module from creating any resources
Required: No

Default value: null

environment (string) optional

ID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'
Required: No

Default value: null

id_length_limit (number) optional

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.


Required: No

Default value: null

label_key_case (string) optional

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.


Required: No

Default value: null

label_order (list(string)) optional

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.


Required: No

Default value: null

label_value_case (string) optional

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.


Required: No

Default value: null

labels_as_tags (set(string)) optional

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.


Required: No

Default value:

[
  "default"
]
name (string) optional

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.


Required: No

Default value: null

namespace (string) optional

ID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique
Required: No

Default value: null

regex_replace_chars (string) optional

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.


Required: No

Default value: null

stage (string) optional

ID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'
Required: No

Default value: null

tags (map(string)) optional

Additional tags (e.g. {'BusinessUnit': 'XYZ'}).
Neither the tag keys nor the tag values will be modified by this module.


Required: No

Default value: { }

tenant (string) optional

ID element (Rarely used, not included by default). A customer identifier, indicating who this instance of a resource is for
Required: No

Default value: null

Outputs​

cluster_address

Cluster address

cluster_configuration_endpoint

Cluster configuration endpoint

cluster_id

Cluster ID

cluster_urls

Cluster URLs

hostname

Cluster hostname

security_group_arn

The ARN of the created security group

security_group_id

The ID of the created security group

security_group_name

The name of the created security group

Dependencies​

Requirements​

  • terraform, version: >= 1.0.0
  • aws, version: >= 5.16
  • null, version: >= 3.0

Providers​

  • aws, version: >= 5.16
  • null, version: >= 3.0

Modules​

NameVersionSourceDescription
aws_security_group2.2.0cloudposse/security-group/awsn/a
dns0.13.0cloudposse/route53-cluster-hostname/awsn/a
this0.25.0cloudposse/label/nulln/a

Resources​

The following resources are used by this module:

Data Sources​

The following data sources are used by this module: