Blue/Green Cluster Module

This module provides the capacity to build a full blue/green clustered stack using either Application Load Balancer or Network Load Balancer.

You can use this module to build a comprehensive, autoscaling stack based on any AMI, which can be rolled out using weighted DNS entries.

It will build the following artifacts:

ALB/NLB

• Blue ALB or NLB
• Green ALB or NLB
• Security groups for Blue ALB
• Security groups for Green ALb
• Route53 DNS entries for Blue ALB/NLB
• Route53 DNS entries for Green ALB/NLB

Cluster Instances

• Blue ASG
• Green ASG
• Blue Launch Configuration
• Green Launch Configuration
• Blue instances (launched by ASG)
• Green instances (launched by ASG)
• Blue instance security groups
• Green instance security groups
• Basic scaling policies

Logging

• S3 bucket for ALB logs
• Cloudwatch Logs Streams for applications

IAM

• Basic IAM Roles for cluster instances

Implementation

Please see the following projects for implementation examples:

Using ALB

• terraform-aws-nodejs-webapp-blue-green
• terraform-aws-nginx-proxy-blue-green

Using NLB

• terraform-aws-squid-proxy-blue-green

Inputs

Name	Description	Type	Default	Required
blue_alb_http_tcp_listeners	The HTTP/TCP listeners to attach to the blue ALB	list	<list>	no
blue_alb_http_tcp_listeners_count	The number of HTTP/TCP listeners to attach the blue ALB	string	"0"	no
blue_alb_https_listeners	The listeners to attach to the blue ALB	list	<list>	no
blue_alb_https_listeners_count	The number of HTTPS listeners to attach the blue ALB	string	"0"	no
blue_application_ports	The ports the ALB should be able to connect to the blue cluster on	list	<list>	no
blue_desired_capacity	The number of instances to put into the blue cluster	string	"1"	no
blue_desired_capacity_start	How many instances to start when the ASG start hook is triggered	string	n/a	yes
blue_desired_capacity_stop	How many instances to stop when the ASG stop hook is triggered	string	n/a	yes
blue_external_alb_target_groups	The target groups to attach to the blue ALB	list	<list>	no
blue_external_alb_target_groups_count	The number of target groups to attach to the blue ALB	string	"0"	no
blue_external_nlb_target_groups	The target groups to attach to the blue ALB	list	<list>	no
blue_external_nlb_target_groups_count	The number of target groups to attach to the blue ALB	string	"0"	no
blue_image_id	The AMI ID to use for the blue cluster	string	n/a	yes
blue_instance_type	The instance type to use for the blue cluster	string	"t2.small"	no
blue_internal_alb_target_groups	The target groups to attach to the blue ALB	list	<list>	no
blue_internal_alb_target_groups_count	The number of target groups to attach to the blue ALB	string	"0"	no
blue_internal_nlb_target_groups	The target groups to attach to the blue ALB	list	<list>	no
blue_internal_nlb_target_groups_count	The number of target groups to attach to the blue ALB	string	"0"	no
blue_max_size	The number of instances to put into the blue cluster	string	"1"	no
blue_max_size_start	How many instances to start when the ASG start hook is triggered	string	n/a	yes
blue_max_size_stop	How many instances to stop when the ASG stop hook is triggered	string	n/a	yes
blue_min_size	The number of instances to put into the blue cluster	string	"1"	no
blue_min_size_start	How many instances to start when the ASG start hook is triggered	string	n/a	yes
blue_min_size_stop	How many instances to stop when the ASG stop hook is triggered	string	n/a	yes
blue_nlb_http_tcp_listeners	The HTTP/TCP listeners to attach to the blue NLB	list	<list>	no
blue_nlb_http_tcp_listeners_count	The number of HTTP/TCP listeners to attach the blue NLB	string	"0"	no
blue_nlb_https_listeners	The listeners to attach to the blue NLB	list	<list>	no
blue_nlb_https_listeners_count	The number of HTTPS listeners to attach the blue NLB	string	"0"	no
blue_recurrence_start	When to start the instances	string	"false"	no
blue_recurrence_stop	When to stop the instances	string	"false"	no
blue_route53_aliases_name	List of ALB Route53 aliases	list	<list>	no
blue_version_tag	The version of the blue product release	string	n/a	yes
blue_wait_for_capacity_timeout	How long to wait before timing out introducing the new green ASG instances	string	"0"	no
blue_weight	Weight of the DNS record for the blue cluster	string	n/a	yes
cluster_name	What to name the blue/green cluster and all of its associated resources	string	n/a	yes
cost_code	The code for the costing	string	n/a	yes
external_alb_computed_egress_with_cidr_blocks	List of objects describing the egress cidr blocks rules permitted for the cluster albs	list	<list>	no
external_alb_computed_egress_with_source_security_group_id	List of objects describing the inbound security group rules permitted on the albs for the cluster	list	<list>	no
external_alb_computed_ingress_with_cidr_blocks	List of objects describing the ingress cidr blocks rules permitted for the loadbalancer	list	<list>	no
external_alb_computed_ingress_with_source_security_group_id	List of objects describing the inbound security group rules permitted on the albs for the cluster albs	list	<list>	no
external_alb_enabled	Whether to create an external ALB or not	string	"true"	no
external_alb_number_of_computed_egress_with_cidr_blocks	The count of computed egress cidr blocks for the cluster albs	string	"0"	no
external_alb_number_of_computed_egress_with_source_security_group_id	The count of computed egress security groups by ID for the cluster albs	string	"0"	no
external_alb_number_of_computed_ingress_with_cidr_blocks	The count of computed ingress cidr blocks for the cluster albs	string	"0"	no
external_alb_number_of_computed_ingress_with_source_security_group_id	The count of computed ingress security groups by ID for the cluster albs	string	"0"	no
external_alb_route53_zone_id	The route 53 zone ID to use for the ALB DNS entries	string	""	no
external_alb_security_groups	Attach security groups directly to the ALB by their ID	list	<list>	no
external_alb_subnet_ids	An list of subnet ID to attach the ELB to which are within the specified VPC	string	""	no
external_nlb_enabled	Whether to create an NLB or not	string	"false"	no
external_nlb_route53_zone_id	The route 53 zone ID to use for the NLB DNS entries	string	""	no
external_nlb_subnet_ids	An list of subnet ID to attach the ELB to which are within the specified VPC	string	""	no
green_alb_http_tcp_listeners	The HTTP/TCP listeners to attach to the green ALB	list	<list>	no
green_alb_http_tcp_listeners_count	The number of HTTP/TCP listeners to attach the green ALB	string	"0"	no
green_alb_https_listeners	The listeners to attach to the green ALB	list	<list>	no
green_alb_https_listeners_count	The number of HTTPS listeners to attach the green ALB	string	"0"	no
green_application_ports	The ports the ALB should be able to connect to the green cluster on	list	<list>	no
green_desired_capacity	The number of instances to put into the green cluster	string	"1"	no
green_desired_capacity_start	How many instances to start when the ASG start hook is triggered	string	n/a	yes
green_desired_capacity_stop	How many instances to stop when the ASG stop hook is triggered	string	n/a	yes
green_external_alb_target_groups	The target groups to attach to the green ALB	list	<list>	no
green_external_alb_target_groups_count	The number of target groups to attach to the green ALB	string	"0"	no
green_external_nlb_target_groups	The target groups to attach to the green NLB	list	<list>	no
green_external_nlb_target_groups_count	The number of target groups to attach to the green NLB	string	"0"	no
green_image_id	The AMI ID to use for the green cluster	string	n/a	yes
green_instance_type	The instance type to use for the green cluster	string	"t2.small"	no
green_internal_alb_target_groups	The target groups to attach to the green ALB	list	<list>	no
green_internal_alb_target_groups_count	The number of target groups to attach to the green ALB	string	"0"	no
green_internal_nlb_target_groups	The target groups to attach to the green NLB	list	<list>	no
green_internal_nlb_target_groups_count	The number of target groups to attach to the green NLB	string	"0"	no
green_max_size	The number of instances to put into the green cluster	string	"1"	no
green_max_size_start	How many instances to start when the ASG start hook is triggered	string	n/a	yes
green_max_size_stop	How many instances to stop when the ASG stop hook is triggered	string	n/a	yes
green_min_size	The number of instances to put into the green cluster	string	"1"	no
green_min_size_start	How many instances to start when the ASG start hook is triggered	string	n/a	yes
green_min_size_stop	How many instances to stop when the ASG stop hook is triggered	string	n/a	yes
green_nlb_http_tcp_listeners	The HTTP/TCP listeners to attach to the green NLB	list	<list>	no
green_nlb_http_tcp_listeners_count	The number of HTTP/TCP listeners to attach the green NLB	string	"0"	no
green_nlb_https_listeners	The listeners to attach to the green NLB	list	<list>	no
green_nlb_https_listeners_count	The number of HTTPS listeners to attach the green NLB	string	"0"	no
green_recurrence_start	When to start the green instances	string	"false"	no
green_recurrence_stop	When to stop the green instances	string	"false"	no
green_route53_aliases_name	List of ALB Route53 aliases	list	<list>	no
green_target_groups	The target groups to attach to the green ALB	list	<list>	no
green_target_groups_count	The number of target groups to attach to the green ALB	string	"0"	no
green_version_tag	The version of the green product release	string	n/a	yes
green_wait_for_capacity_timeout	How long to wait before timing out introducing the new green ASG instances	string	"0"	no
green_weight	Weight of the DNS record for the green cluster	string	n/a	yes
iam_policies	The IAM policies to attach to the IAM role for the cluster instances	list	<list>	no
instance_computed_egress_with_cidr_blocks	List of objects describing the egress cidr blocks rules permitted for the cluster instances	list	<list>	no
instance_computed_egress_with_source_security_group_id	List of objects describing the inbound security group rules permitted on the instances for the cluster	list	<list>	no
instance_computed_ingress_with_cidr_blocks	List of objects describing the ingress cidr blocks rules permitted for the loadbalancer	list	<list>	no
instance_computed_ingress_with_source_security_group_id	List of objects describing the inbound security group rules permitted on the instances for the cluster instances	list	<list>	no
instance_number_of_computed_egress_with_cidr_blocks	The count of computed egress cidr blocks for the cluster instances	string	"0"	no
instance_number_of_computed_egress_with_source_security_group_id	The count of computed egress security groups by ID for the cluster instances	string	"0"	no
instance_number_of_computed_ingress_with_cidr_blocks	The count of computed ingress cidr blocks for the cluster instances	string	"0"	no
instance_number_of_computed_ingress_with_source_security_group_id	The count of computed ingress security groups by ID for the cluster instances	string	"0"	no
instance_route53_zone_id	The route 53 zone ID to use for the instance DNS entries	string	n/a	yes
instance_security_groups	Attach security groups directly to the instances by their ID	list	<list>	no
instance_subnet_ids	An list of subnet IDs which are within the specified VPC	list	<list>	no
internal_alb_computed_egress_with_cidr_blocks	List of objects describing the egress cidr blocks rules permitted for the cluster albs	list	<list>	no
internal_alb_computed_egress_with_source_security_group_id	List of objects describing the inbound security group rules permitted on the albs for the cluster	list	<list>	no
internal_alb_computed_ingress_with_cidr_blocks	List of objects describing the ingress cidr blocks rules permitted for the loadbalancer	list	<list>	no
internal_alb_computed_ingress_with_source_security_group_id	List of objects describing the inbound security group rules permitted on the albs for the cluster albs	list	<list>	no
internal_alb_enabled	Whether to create an internal ALB or not	string	"true"	no
internal_alb_number_of_computed_egress_with_cidr_blocks	The count of computed egress cidr blocks for the cluster albs	string	"0"	no
internal_alb_number_of_computed_egress_with_source_security_group_id	The count of computed egress security groups by ID for the cluster albs	string	"0"	no
internal_alb_number_of_computed_ingress_with_cidr_blocks	The count of computed ingress cidr blocks for the cluster albs	string	"0"	no
internal_alb_number_of_computed_ingress_with_source_security_group_id	The count of computed ingress security groups by ID for the cluster albs	string	"0"	no
internal_alb_route53_zone_id	The route 53 zone ID to use for the ALB DNS entries	string	""	no
internal_alb_security_groups	Attach security groups directly to the ALB by their ID	list	<list>	no
internal_alb_subnet_ids	An list of subnet ID to attach the ELB to which are within the specified VPC	string	""	no
internal_nlb_enabled	Whether to create an NLB or not	string	"false"	no
internal_nlb_route53_zone_id	The route 53 zone ID to use for the NLB DNS entries	string	""	no
internal_nlb_subnet_ids	An list of subnet ID to attach the ELB to which are within the specified VPC	string	""	no
owner	Product owner email address	string	n/a	yes
product	Product	string	n/a	yes
product_family	The product family of the project, e.g. FA	string	n/a	yes
role	Role of the product within the account	string	n/a	yes
ssh_key_name	The name of an EC2 Key Pair that can be used to SSH to the EC2 Instances in this cluster. Set to an empty string to not associate a Key Pair.	string	""	no
tags	Additional tags to add to the cluster.	list	<list>	no
vpc_id	The ID of the VPC to launch the instances into	string	n/a	yes

Outputs

Name	Description
blue_external_alb_dns_name
blue_external_alb_http_tcp_listener_arns
blue_external_alb_http_tcp_listener_ids
blue_external_alb_https_listener_arns
blue_external_alb_https_listener_ids
blue_external_alb_load_balancer_arn_suffix
blue_external_alb_load_balancer_id
blue_external_alb_load_balancer_zone_id
blue_external_alb_security_group_id
blue_external_alb_target_group_arn_suffixes
blue_external_alb_target_group_arns
blue_external_alb_target_group_names
blue_external_nlb_dns_name
blue_external_nlb_http_tcp_listener_arns
blue_external_nlb_http_tcp_listener_ids
blue_external_nlb_https_listener_arns
blue_external_nlb_https_listener_ids
blue_external_nlb_load_balancer_arn_suffix
blue_external_nlb_load_balancer_id
blue_external_nlb_load_balancer_zone_id
blue_external_nlb_target_group_arn_suffixes
blue_external_nlb_target_group_arns
blue_external_nlb_target_group_names
blue_internal_alb_dns_name
blue_internal_alb_http_tcp_listener_arns
blue_internal_alb_http_tcp_listener_ids
blue_internal_alb_https_listener_arns
blue_internal_alb_https_listener_ids
blue_internal_alb_load_balancer_arn_suffix
blue_internal_alb_load_balancer_id
blue_internal_alb_load_balancer_zone_id
blue_internal_alb_security_group_id
blue_internal_alb_target_group_arn_suffixes
blue_internal_alb_target_group_arns
blue_internal_alb_target_group_names
blue_internal_nlb_dns_name
blue_internal_nlb_http_tcp_listener_arns
blue_internal_nlb_http_tcp_listener_ids
blue_internal_nlb_https_listener_arns
blue_internal_nlb_https_listener_ids
blue_internal_nlb_load_balancer_arn_suffix
blue_internal_nlb_load_balancer_id
blue_internal_nlb_load_balancer_zone_id
blue_internal_nlb_target_group_arn_suffixes
blue_internal_nlb_target_group_arns
blue_internal_nlb_target_group_names
cluster_security_group_id
external_alb_weighted_dns_name
external_alb_weighted_fqdn
external_nlb_weighted_dns_name
external_nlb_weighted_fqdn
green_external_alb_dns_name
green_external_alb_http_tcp_listener_arns
green_external_alb_http_tcp_listener_ids
green_external_alb_https_listener_arns
green_external_alb_https_listener_ids
green_external_alb_load_balancer_arn_suffix
green_external_alb_load_balancer_id
green_external_alb_load_balancer_zone_id
green_external_alb_security_group_id
green_external_alb_target_group_arn_suffixes
green_external_alb_target_group_arns
green_external_alb_target_group_names
green_external_nlb_dns_name
green_external_nlb_http_tcp_listener_arns
green_external_nlb_http_tcp_listener_ids
green_external_nlb_https_listener_arns
green_external_nlb_https_listener_ids
green_external_nlb_load_balancer_arn_suffix
green_external_nlb_load_balancer_id
green_external_nlb_load_balancer_zone_id
green_external_nlb_target_group_arn_suffixes
green_external_nlb_target_group_arns
green_external_nlb_target_group_names
green_internal_alb_dns_name
green_internal_alb_http_tcp_listener_arns
green_internal_alb_http_tcp_listener_ids
green_internal_alb_https_listener_arns
green_internal_alb_https_listener_ids
green_internal_alb_load_balancer_arn_suffix
green_internal_alb_load_balancer_id
green_internal_alb_load_balancer_zone_id
green_internal_alb_security_group_id
green_internal_alb_target_group_arn_suffixes
green_internal_alb_target_group_arns
green_internal_alb_target_group_names
green_internal_nlb_dns_name
green_internal_nlb_http_tcp_listener_arns
green_internal_nlb_http_tcp_listener_ids
green_internal_nlb_https_listener_arns
green_internal_nlb_https_listener_ids
green_internal_nlb_load_balancer_arn_suffix
green_internal_nlb_load_balancer_id
green_internal_nlb_load_balancer_zone_id
green_internal_nlb_target_group_arn_suffixes
green_internal_nlb_target_group_arns
green_internal_nlb_target_group_names
instance_iam_role_arn
instance_security_group_id
internal_alb_weighted_dns_name
internal_alb_weighted_fqdn
internal_nlb_weighted_dns_name
internal_nlb_weighted_fqdn