mig

Managed Instance Group (MIG)

This module is used to create a google_compute_region_instance_group_manager, and optionally, an autoscaler and healthchecks.

Usage

See the simple example for a usage example.

Upgrading

The current version is 2.X. The following guides are available to assist with upgrades:

• 1.X -> 2.0

Inputs

Name	Description	Type	Default	Required
autoscaler_name	Autoscaler name. When variable is empty, name will be derived from var.hostname.	string	""	no
autoscaling_cpu	Autoscaling, cpu utilization policy block as single element array. https://www.terraform.io/docs/providers/google/r/compute_autoscaler.html#cpu_utilization	list(map(number))	[]	no
autoscaling_enabled	Creates an autoscaler for the managed instance group	string	"false"	no
autoscaling_lb	Autoscaling, load balancing utilization policy block as single element array. https://www.terraform.io/docs/providers/google/r/compute_autoscaler.html#load_balancing_utilization	list(map(number))	[]	no
autoscaling_metric	Autoscaling, metric policy block as single element array. https://www.terraform.io/docs/providers/google/r/compute_autoscaler.html#metric	list(object({ name = string target = number type = string }))	[]	no
autoscaling_mode	Operating mode of the autoscaling policy. If omitted, the default value is ON. https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/compute_autoscaler#mode	string	null	no
autoscaling_scale_in_control	Autoscaling, scale-in control block. https://www.terraform.io/docs/providers/google/r/compute_autoscaler.html#scale_in_control	object({ fixed_replicas = number percent_replicas = number time_window_sec = number })	{ "fixed_replicas": null, "percent_replicas": null, "time_window_sec": null }	no
cooldown_period	The number of seconds that the autoscaler should wait before it starts collecting information from a new instance.	number	60	no
distribution_policy_zones	The distribution policy, i.e. which zone(s) should instances be create in. Default is all zones in given region.	list(string)	[]	no
health_check	Health check to determine whether instances are responsive and able to do work	object({ type = string initial_delay_sec = number check_interval_sec = number healthy_threshold = number timeout_sec = number unhealthy_threshold = number response = string proxy_header = string port = number request = string request_path = string host = string })	{ "check_interval_sec": 30, "healthy_threshold": 1, "host": "", "initial_delay_sec": 30, "port": 80, "proxy_header": "NONE", "request": "", "request_path": "/", "response": "", "timeout_sec": 10, "type": "", "unhealthy_threshold": 5 }	no
health_check_name	Health check name. When variable is empty, name will be derived from var.hostname.	string	""	no
hostname	Hostname prefix for instances	string	"default"	no
instance_template	Instance template self_link used to create compute instances	any	n/a	yes
max_replicas	The maximum number of instances that the autoscaler can scale up to. This is required when creating or updating an autoscaler. The maximum number of replicas should not be lower than minimal number of replicas.	number	10	no
mig_name	Managed instance group name. When variable is empty, name will be derived from var.hostname.	string	""	no
mig_timeouts	Times for creation, deleting and updating the MIG resources. Can be helpful when using wait_for_instances to allow a longer VM startup time.	object({ create = string update = string delete = string })	{ "create": "5m", "delete": "15m", "update": "5m" }	no
min_replicas	The minimum number of replicas that the autoscaler can scale down to. This cannot be less than 0.	number	2	no
named_ports	Named name and named port. https://cloud.google.com/load-balancing/docs/backend-service#named_ports	list(object({ name = string port = number }))	[]	no
network	Network to deploy to. Only one of network or subnetwork should be specified.	string	""	no
project_id	The GCP project ID	string	null	no
region	The GCP region where the managed instance group resides.	any	n/a	yes
stateful_disks	Disks created on the instances that will be preserved on instance delete. https://cloud.google.com/compute/docs/instance-groups/configuring-stateful-disks-in-migs	list(object({ device_name = string delete_rule = string }))	[]	no
subnetwork	Subnet to deploy to. Only one of network or subnetwork should be specified.	string	""	no
subnetwork_project	The project that subnetwork belongs to	string	""	no
target_pools	The target load balancing pools to assign this group to.	list(string)	[]	no
target_size	The target number of running instances for this managed instance group. This value should always be explicitly set unless this resource is attached to an autoscaler, in which case it should never be set.	number	1	no
update_policy	The rolling update policy. https://www.terraform.io/docs/providers/google/r/compute_region_instance_group_manager.html#rolling_update_policy	list(object({ max_surge_fixed = number instance_redistribution_type = string max_surge_percent = number max_unavailable_fixed = number max_unavailable_percent = number min_ready_sec = number replacement_method = string minimal_action = string type = string }))	[]	no
wait_for_instances	Whether to wait for all instances to be created/updated before returning. Note that if this is set to true and the operation does not succeed, Terraform will continue trying until it times out.	string	"false"	no

Outputs

Name	Description
health_check_self_links	All self_links of healthchecks created for the instance group.
instance_group	Instance-group url of managed instance group
instance_group_manager	An instance of google_compute_region_instance_group_manager of the instance group.
self_link	Self-link of managed instance group