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msk

This component is responsible for provisioning Amazon Managed Streaming clusters for Apache Kafka.

Usage​

Stack Level: Regional

Here's an example snippet for how to use this component.

components:
  terraform:
    msk:
      metadata:
        component: "msk"
      vars:
        enabled: true
        name: "msk"
        vpc_component_name: "vpc"
        dns_delegated_component_name: "dns-delegated"
        dns_delegated_environment_name: "gbl"
        # https://docs.aws.amazon.com/msk/latest/developerguide/supported-kafka-versions.html
        kafka_version: "3.4.0"
        public_access_enabled: false
        # https://aws.amazon.com/msk/pricing/
        broker_instance_type: "kafka.m5.large"
        # Number of brokers per AZ
        broker_per_zone: 1
        #  `broker_dns_records_count` specifies how many DNS records to create for the broker endpoints in the DNS zone provided in the `zone_id` variable.
        #  This corresponds to the total number of broker endpoints created by the module.
        #  Calculate this number by multiplying the `broker_per_zone` variable by the subnet count.
        broker_dns_records_count: 3
        broker_volume_size: 500
        client_broker: "TLS_PLAINTEXT"
        encryption_in_cluster: true
        encryption_at_rest_kms_key_arn: ""
        enhanced_monitoring: "DEFAULT"
        certificate_authority_arns: []

        # Authentication methods
        client_allow_unauthenticated: true
        client_sasl_scram_enabled: false
        client_sasl_scram_secret_association_enabled: false
        client_sasl_scram_secret_association_arns: []
        client_sasl_iam_enabled: false
        client_tls_auth_enabled: false

        jmx_exporter_enabled: false
        node_exporter_enabled: false
        cloudwatch_logs_enabled: false
        firehose_logs_enabled: false
        firehose_delivery_stream: ""
        s3_logs_enabled: false
        s3_logs_bucket: ""
        s3_logs_prefix: ""
        properties: {}
        autoscaling_enabled: true
        storage_autoscaling_target_value: 60
        storage_autoscaling_max_capacity: null
        storage_autoscaling_disable_scale_in: false
        create_security_group: true
        security_group_rule_description: "Allow inbound %s traffic"
        # A list of IDs of Security Groups to allow access to the cluster security group
        allowed_security_group_ids: []
        # A list of IPv4 CIDRs to allow access to the cluster security group
        allowed_cidr_blocks: []

Variables​

Required Variables​

broker_instance_type (string) required

The instance type to use for the Kafka brokers

kafka_version (string) required

The desired Kafka software version.
Refer to https://docs.aws.amazon.com/msk/latest/developerguide/supported-kafka-versions.html for more details


region (string) required

AWS region

vpc_component_name (string) required

The name of the Atmos VPC component

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(s) 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.
For more info see https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule
and https://github.com/cloudposse/terraform-aws-security-group.



Default value: [ ]

allow_all_egress (bool) optional

If true, the created security group will allow egress on all ports and protocols to all IP addresses.
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_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: [ ]

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: [ ]

autoscaling_enabled (bool) optional

To automatically expand your cluster's storage in response to increased usage, you can enable this. More info


Default value: true

broker_dns_records_count (number) optional

This variable specifies how many DNS records to create for the broker endpoints in the DNS zone provided in the zone_id variable.
This corresponds to the total number of broker endpoints created by the module.
Calculate this number by multiplying the broker_per_zone variable by the subnet count.
This variable is necessary to prevent the Terraform error:
The "count" value depends on resource attributes that cannot be determined until apply, so Terraform cannot predict how many instances will be created.



Default value: 0

broker_per_zone (number) optional

Number of Kafka brokers per zone


Default value: 1

broker_volume_size (number) optional

The size in GiB of the EBS volume for the data drive on each broker node


Default value: 1000

certificate_authority_arns (list(string)) optional

List of ACM Certificate Authority Amazon Resource Names (ARNs) to be used for TLS client authentication


Default value: [ ]

client_allow_unauthenticated (bool) optional

Enable unauthenticated access


Default value: false

client_broker (string) optional

Encryption setting for data in transit between clients and brokers. Valid values: TLS, TLS_PLAINTEXT, and PLAINTEXT


Default value: "TLS"

client_sasl_iam_enabled (bool) optional

Enable client authentication via IAM policies. Cannot be set to true at the same time as client_tls_auth_enabled


Default value: false

client_sasl_scram_enabled (bool) optional

Enable SCRAM client authentication via AWS Secrets Manager. Cannot be set to true at the same time as client_tls_auth_enabled


Default value: false

client_sasl_scram_secret_association_arns (list(string)) optional

List of AWS Secrets Manager secret ARNs for SCRAM authentication


Default value: [ ]

client_sasl_scram_secret_association_enabled (bool) optional

Enable the list of AWS Secrets Manager secret ARNs for SCRAM authentication


Default value: true

client_tls_auth_enabled (bool) optional

Set true to enable the Client TLS Authentication


Default value: false

cloudwatch_logs_enabled (bool) optional

Indicates whether you want to enable or disable streaming broker logs to Cloudwatch Logs


Default value: false

cloudwatch_logs_log_group (string) optional

Name of the Cloudwatch Log Group to deliver logs to


Default value: null

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

custom_broker_dns_name (string) optional

Custom Route53 DNS hostname for MSK brokers. Use %%ID%% key to specify brokers index in the hostname. Example: kafka-broker%%ID%%.example.com


Default value: null

dns_delegated_component_name (string) optional

The component name of dns-delegated


Default value: "dns-delegated"

dns_delegated_environment_name (string) optional

The environment name of dns-delegated


Default value: "gbl"

encryption_at_rest_kms_key_arn (string) optional

You may specify a KMS key short ID or ARN (it will always output an ARN) to use for encrypting your data at rest


Default value: ""

encryption_in_cluster (bool) optional

Whether data communication among broker nodes is encrypted


Default value: true

enhanced_monitoring (string) optional

Specify the desired enhanced MSK CloudWatch monitoring level. Valid values: DEFAULT, PER_BROKER, and PER_TOPIC_PER_BROKER


Default value: "DEFAULT"

firehose_delivery_stream (string) optional

Name of the Kinesis Data Firehose delivery stream to deliver logs to


Default value: ""

firehose_logs_enabled (bool) optional

Indicates whether you want to enable or disable streaming broker logs to Kinesis Data Firehose


Default value: false

inline_rules_enabled (bool) optional

NOT RECOMMENDED. Create rules "inline" instead of as separate aws_security_group_rule resources.
See #20046 for one of several issues with inline rules.
See this post for details on the difference between inline rules and rule resources.



Default value: false

jmx_exporter_enabled (bool) optional

Set true to enable the JMX Exporter


Default value: false

node_exporter_enabled (bool) optional

Set true to enable the Node Exporter


Default value: false

preserve_security_group_id (bool) optional

When false and security_group_create_before_destroy is true, changes to security group rules
cause a new security group to be created with the new rules, and the existing security group is then
replaced with the new one, eliminating any service interruption.
When true or when changing the value (from false to true or from true to false),
existing security group rules will be deleted before new ones are created, resulting in a service interruption,
but preserving the security group itself.
NOTE: Setting this to true does not guarantee the security group will never be replaced,
it only keeps changes to the security group rules from triggering a replacement.
See the terraform-aws-security-group README for further discussion.



Default value: false

properties (map(string)) optional

Contents of the server.properties file. Supported properties are documented in the MSK Developer Guide


Default value: { }

public_access_enabled (bool) optional

Enable public access to MSK cluster (given that all of the requirements are met)


Default value: false

s3_logs_bucket (string) optional

Name of the S3 bucket to deliver logs to


Default value: ""

s3_logs_enabled (bool) optional

Indicates whether you want to enable or disable streaming broker logs to S3


Default value: false

s3_logs_prefix (string) optional

Prefix to append to the S3 folder name logs are delivered to


Default value: ""

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 importing an existing security group
that you do not want replaced and therefore need full control over its name.
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 from
lingering ENIs left by certain AWS services such as Elastic Load Balancing.



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: "Managed by Terraform"

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: [ ]

security_group_rule_description (string) optional

The description to place on each security group rule. The %s will be replaced with the protocol name


Default value: "Allow inbound %s traffic"

storage_autoscaling_disable_scale_in (bool) optional

If the value is true, scale in is disabled and the target tracking policy won't remove capacity from the scalable resource


Default value: false

storage_autoscaling_max_capacity (number) optional

Maximum size the autoscaling policy can scale storage. Defaults to broker_volume_size


Default value: null

storage_autoscaling_target_value (number) optional

Percentage of storage used to trigger autoscaled storage increase


Default value: 60

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​

bootstrap_brokers

Comma separated list of one or more hostname:port pairs of Kafka brokers suitable to bootstrap connectivity to the Kafka cluster

bootstrap_brokers_public_sasl_iam

Comma separated list of one or more DNS names (or IP addresses) and SASL IAM port pairs for public access to the Kafka cluster using SASL/IAM

bootstrap_brokers_public_sasl_scram

Comma separated list of one or more DNS names (or IP addresses) and SASL SCRAM port pairs for public access to the Kafka cluster using SASL/SCRAM

bootstrap_brokers_public_tls

Comma separated list of one or more DNS names (or IP addresses) and TLS port pairs for public access to the Kafka cluster using TLS

bootstrap_brokers_sasl_iam

Comma separated list of one or more DNS names (or IP addresses) and SASL IAM port pairs for access to the Kafka cluster using SASL/IAM

bootstrap_brokers_sasl_scram

Comma separated list of one or more DNS names (or IP addresses) and SASL SCRAM port pairs for access to the Kafka cluster using SASL/SCRAM

bootstrap_brokers_tls

Comma separated list of one or more DNS names (or IP addresses) and TLS port pairs for access to the Kafka cluster using TLS

broker_endpoints

List of broker endpoints

cluster_arn

Amazon Resource Name (ARN) of the MSK cluster

cluster_name

The cluster name of the MSK cluster

config_arn

Amazon Resource Name (ARN) of the MSK configuration

current_version

Current version of the MSK Cluster

hostnames

List of MSK Cluster broker DNS hostnames

latest_revision

Latest revision of the MSK configuration

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

storage_mode

Storage mode for supported storage tiers

zookeeper_connect_string

Comma separated list of one or more hostname:port pairs to connect to the Apache Zookeeper cluster

zookeeper_connect_string_tls

Comma separated list of one or more hostname:port pairs to connect to the Apache Zookeeper cluster via TLS

Dependencies​

Requirements​

  • terraform, version: >= 1.0.0
  • aws, version: >= 4.9.0

Modules​

NameVersionSourceDescription
dns_delegated1.5.0cloudposse/stack-config/yaml//modules/remote-staten/a
iam_roleslatest../account-map/modules/iam-rolesn/a
kafka2.3.0cloudposse/msk-apache-kafka-cluster/awsn/a
this0.25.0cloudposse/label/nulln/a
vpc1.5.0cloudposse/stack-config/yaml//modules/remote-staten/a

References​