dynamic_backends

Global HTTP Load Balancer Terraform Module

Modular Global HTTP Load Balancer for GCE using forwarding rules.

This submodule allows for configuring dynamic backend outside Terraform. As such, any changes to the backends.groups variable after creation will be ignored.

Load Balancer Types

• TCP load balancer
• HTTP/S load balancer
• Internal load balancer

Compatibility

This module is meant for use with Terraform 1.3+ and tested using Terraform 1.3. If you find incompatibilities using Terraform >=1.3, please open an issue. If you haven't upgraded and need a Terraform 0.12.x-compatible version of this module, the last released version intended for Terraform 0.12.x is v4.5.0.

Version

Current version is 9.0. Upgrade guides:

• 2.X -> 3.0
• 3.X -> 4.0
• 6.X -> 7.0
• 7.X -> 8.0
• 8.X -> 9.0
• 9.X -> 10.0

Usage

module "gce-lb-http" {
  source            = "GoogleCloudPlatform/lb-http/google//modules/dynamic_backends"
  version           = "~> 9.0"

  project           = "my-project-id"
  name              = "group-http-lb"
  target_tags       = [module.mig1.target_tags, module.mig2.target_tags]
  backends = {
    default = {
      port                            = var.service_port
      protocol                        = "HTTP"
      port_name                       = var.service_port_name
      timeout_sec                     = 10
      enable_cdn                      = false


      health_check = {
        request_path        = "/"
        port                = var.service_port
      }

      log_config = {
        enable = true
        sample_rate = 1.0
      }

      groups = [
        {
          # Each node pool instance group should be added to the backend.
          group                        = var.backend
        },
      ]

      iap_config = {
        enable               = false
      }
    }
  }
}

Resources created

Figure 1. diagram of terraform resources

Inputs

Name	Description	Type	Default	Required
address	Existing IPv4 address to use (the actual IP address value)	string	null	no
backends	Map backend indices to list of backend maps.	map(object({ port = optional(number) project = optional(string) protocol = optional(string) port_name = optional(string) description = optional(string) enable_cdn = optional(bool) compression_mode = optional(string) security_policy = optional(string, null) edge_security_policy = optional(string, null) custom_request_headers = optional(list(string)) custom_response_headers = optional(list(string)) timeout_sec = optional(number) connection_draining_timeout_sec = optional(number) session_affinity = optional(string) affinity_cookie_ttl_sec = optional(number) locality_lb_policy = optional(string) health_check = optional(object({ host = optional(string) request_path = optional(string) request = optional(string) response = optional(string) port = optional(number) port_name = optional(string) proxy_header = optional(string) port_specification = optional(string) protocol = optional(string) check_interval_sec = optional(number) timeout_sec = optional(number) healthy_threshold = optional(number) unhealthy_threshold = optional(number) logging = optional(bool) })) log_config = object({ enable = optional(bool) sample_rate = optional(number) }) groups = list(object({ group = string description = optional(string) balancing_mode = optional(string) capacity_scaler = optional(number) max_connections = optional(number) max_connections_per_instance = optional(number) max_connections_per_endpoint = optional(number) max_rate = optional(number) max_rate_per_instance = optional(number) max_rate_per_endpoint = optional(number) max_utilization = optional(number) })) iap_config = optional(object({ enable = bool oauth2_client_id = optional(string) oauth2_client_secret = optional(string) })) cdn_policy = optional(object({ cache_mode = optional(string) signed_url_cache_max_age_sec = optional(string) default_ttl = optional(number) max_ttl = optional(number) client_ttl = optional(number) negative_caching = optional(bool) negative_caching_policy = optional(object({ code = optional(number) ttl = optional(number) })) serve_while_stale = optional(number) cache_key_policy = optional(object({ include_host = optional(bool) include_protocol = optional(bool) include_query_string = optional(bool) query_string_blacklist = optional(list(string)) query_string_whitelist = optional(list(string)) include_http_headers = optional(list(string)) include_named_cookies = optional(list(string)) })) bypass_cache_on_request_headers = optional(list(string)) })) outlier_detection = optional(object({ base_ejection_time = optional(object({ seconds = number nanos = optional(number) })) consecutive_errors = optional(number) consecutive_gateway_failure = optional(number) enforcing_consecutive_errors = optional(number) enforcing_consecutive_gateway_failure = optional(number) enforcing_success_rate = optional(number) interval = optional(object({ seconds = number nanos = optional(number) })) max_ejection_percent = optional(number) success_rate_minimum_hosts = optional(number) success_rate_request_volume = optional(number) success_rate_stdev_factor = optional(number) })) }))	{}	no
create_address	Create a new global IPv4 address	bool	true	no
create_ipv6_address	Allocate a new IPv6 address. Conflicts with "ipv6_address" - if both specified, "create_ipv6_address" takes precedence.	bool	false	no
create_url_map	Set to false if url_map variable is provided.	bool	false	no
edge_security_policy	The resource URL for the edge security policy to associate with the backend service	string	null	no
enable_ipv6	Enable IPv6 address on the CDN load-balancer	bool	false	no
firewall_networks	Names of the networks to create firewall rules in	list(string)	[]	no
firewall_projects	Names of the projects to create firewall rules in	list(string)	[]	no
http_forward	Set to false to disable HTTP port 80 forward	bool	true	no
http_keep_alive_timeout_sec	Specifies how long to keep a connection open, after completing a response, while there is no matching traffic (in seconds).	number	null	no
http_port	The port for the HTTP load balancer	number	80	no
https_port	The port for the HTTPS load balancer	number	443	no
https_redirect	Set to true to enable https redirect on the lb.	bool	true	no
ipv6_address	An existing IPv6 address to use (the actual IP address value)	string	null	no
labels	The labels to attach to resources created by this module	map(string)	{}	no
load_balancing_scheme	Load balancing scheme type (EXTERNAL for classic external load balancer, EXTERNAL_MANAGED for Envoy-based load balancer, and INTERNAL_SELF_MANAGED for traffic director)	string	"EXTERNAL_MANAGED"	no
name	Name for the forwarding rule and prefix for supporting resources	string	"default"	no
network	Network for INTERNAL_SELF_MANAGED load balancing scheme	string	"default"	no
project	The project to deploy to, if not set the default provider project is used.	string	n/a	yes
quic	Specifies the QUIC override policy for this resource. Set true to enable HTTP/3 and Google QUIC support, false to disable both. Defaults to null which enables support for HTTP/3 only.	bool	null	no
security_policy	The resource URL for the security policy to associate with the backend service	string	null	no
server_tls_policy	The resource URL for the server TLS policy to associate with the https proxy service	string	null	no
ssl	Set to true to enable SSL support.	bool	true	no
ssl_policy	Selfink to SSL Policy	string	null	no
target_service_accounts	List of target service accounts for health check firewall rule. Exactly one of target_tags or target_service_accounts should be specified.	list(string)	[]	no
target_tags	List of target tags for health check firewall rule. Exactly one of target_tags or target_service_accounts should be specified.	list(string)	[]	no
url_map	The url_map resource to use. Default is to send all traffic to first backend.	string	null	no

Outputs

Name	Description
backend_services	The backend service resources.
certificate_map	The certificate map used by this module.
external_ip	The external IPv4 assigned to the global fowarding rule.
external_ipv6_address	The external IPv6 assigned to the global fowarding rule.
http_proxy	The HTTP proxy used by this module.
https_proxy	The HTTPS proxy used by this module.
ipv6_enabled	Whether IPv6 configuration is enabled on this load-balancer
url_map	The default URL map used by this module.

• google_compute_global_forwarding_rule.http: The global HTTP forwarding rule.
• google_compute_global_forwarding_rule.https: The global HTTPS forwarding rule created when ssl is true.
• google_compute_target_http_proxy.default: The HTTP proxy resource that binds the url map. Created when input ssl is false.
• google_compute_target_https_proxy.default: The HTTPS proxy resource that binds the url map. Created when input ssl is true.
• google_compute_url_map.default: The default URL map resource when input url_map is not provided.
• google_compute_backend_service.default.*: The backend services created for each of the backend_params elements.
• google_compute_health_check.default.*: Health check resources created for each of the (non global NEG) backend services.
• google_compute_firewall.default-hc: Firewall rule created for each of the backed services to allow health checks to the instance group.