For our ECS service definition we have this snippet at the
`load_balancer`.
The `target_group_arn` is being pupulated by an external service that
returns the arn based on a simple string from our microservices list.
If the arn changed, this would not cause a recreation of the service and
leaving a dangling pointer to an arn that does not exist anymore.
```
load_balancer {
target_group_arn = "${lookup(var.target_group_mapping, element(values(var.microservices), count.index))}"
container_name = "${element(values(var.microservices), count.index)}"
container_port = "${var.container_port}"
}
```
The fix is adding another field to the set that's creating the ELB/ALB
definition. From looking into the git history seems this code was
created prior to ALB thus not having this field available at the time.
Service is being recreated as expected, no other services are affected
(expected behavior)
The Default values set by AWS were breaking the AWS ALB Listener Rule
tests. The stickiness parameter needed to be set to be Computed: true to
remove this discrepancy
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSALBListenerRule_basic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/04/03 01:23:47 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSALBListenerRule_basic -timeout 120m
=== RUN TestAccAWSALBListenerRule_basic
--- PASS: TestAccAWSALBListenerRule_basic (235.36s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 235.397s
```
* provider/aws: New resource: aws_ses_domain_identity
Provide a resource to manage domain identities in SES. Exports the
verification_code attribute which can be used to add the TXT record to
the domain to complete the domain verification.
* provider/aws: Acceptance tests for aws_ses_domain_identity
* Resource aws_ses_domain_identity: Documentation update
Provide documentation for the new resource type.
Fixes: #9959
When we specify that we want an opsworks_instance state of running, we
should wait for that the be the case. This will then allow us to use the
Computed values (e.g. private_ip) etc and allow us to use provisioners
as part of the terraform config
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSOpsworksInstance'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/30 20:55:21 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSOpsworksInstance -timeout 120m
=== RUN TestAccAWSOpsworksInstance_importBasic
--- PASS: TestAccAWSOpsworksInstance_importBasic (72.28s)
=== RUN TestAccAWSOpsworksInstance
--- PASS: TestAccAWSOpsworksInstance (110.17s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 182.479s
```
Fixes: #8847
We actually didn't get the list of tags from the API, therefore, any
manual changes were not actually showing up in subsequent plans
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSALBTargetGroup_basic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/30 15:45:53 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSALBTargetGroup_basic -timeout 120m
=== RUN TestAccAWSALBTargetGroup_basic
--- PASS: TestAccAWSALBTargetGroup_basic (62.76s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 62.787s
```
Fixes: #13167
When changes to the target group were made via CLI or AWS Console, they
were not being picked up by terraform. This is because we were not
catching an error setting the `stickiness` parameters:
```
Error refreshing state: 1 error(s) occurred:
* aws_alb_target_group.test: aws_alb_target_group.test: stickiness.0.enabled: '' expected type 'bool', got unconvertible type 'string'
```
This meant that changes were not picked up in the following plan. The changes mean the following now:
```
~ aws_alb_target_group.test
stickiness.0.cookie_duration: "10440" => "10000"
stickiness.0.enabled: "false" => "true"
Plan: 0 to add, 1 to change, 0 to destroy.
```
Fixes: #13216
Prior to Terraform 0.9.2, we always set placement_strategies to
lowercase. Therefore, people using it in Terraform 0.9.2 are getting
continual diffs:
```
-/+ aws_ecs_service.mongo
cluster: "arn:aws:ecs:us-west-2:187416307283:cluster/terraformecstest1" => "arn:aws:ecs:us-west-2:187416307283:cluster/terraformecstest1"
deployment_maximum_percent: "200" => "200"
deployment_minimum_healthy_percent: "100" => "100"
desired_count: "1" => "1"
name: "mongodb" => "mongodb"
placement_strategy.#: "1" => "1"
placement_strategy.1676812570.field: "instanceid" => "" (forces new resource)
placement_strategy.1676812570.type: "spread" => "" (forces new resource)
placement_strategy.3946258308.field: "" => "instanceId" (forces new resource)
placement_strategy.3946258308.type: "" => "spread" (forces new resource)
task_definition: "arn:aws:ecs:us-west-2:187416307283:task-definition/mongodb:1991" => "arn:aws:ecs:us-west-2:187416307283:task-definition/mongodb:1991"
Plan: 1 to add, 0 to change, 1 to destroy.
```
This adds a DiffSuppression func to make sure this doesn't trigger a
ForceNew resource:
```
% terraform plan ✹ ✭
[WARN] /Users/stacko/Code/go/bin/terraform-provider-aws overrides an internal plugin for aws-provider.
If you did not expect to see this message you will need to remove the old plugin.
See https://www.terraform.io/docs/internals/internal-plugins.html
Refreshing Terraform state in-memory prior to plan...
The refreshed state will be used to calculate this plan, but will not be
persisted to local or remote state storage.
aws_ecs_cluster.default: Refreshing state... (ID: arn:aws:e...ecstest1)
aws_ecs_task_definition.mongo: Refreshing state... (ID: mongodb)
aws_ecs_service.mongo: Refreshing state... (ID: arn:aws:e.../mongodb)
No changes. Infrastructure is up-to-date.
This means that Terraform did not detect any differences between your
configuration and real physical resources that exist. As a result, Terraform
doesn't need to do anything.
```
```
```
* provider/aws: Add Support for maintenance_window and back_window to rds_cluster_instance
Fixes: #9489
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSRDSClusterInstance_basic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/28 23:08:45 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSRDSClusterInstance_basic -timeout 120m
=== RUN TestAccAWSRDSClusterInstance_basic
--- PASS: TestAccAWSRDSClusterInstance_basic (1433.41s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 1433.438s
```
* Update rds_cluster_instance.html.markdown
* Update rds_cluster_instance.html.markdown
It turns out if you're trying to write a config to conditionally restore
an instance from a snapshot, you end up painted into a corner with the
combination of `snapshot_identifier` and `name`.
You need `name` to be specified for DBs you're creating, but when
`snapshot_identifier` is populated you need it to be blank or else the
AWS API throws an error.
The logical next step is to drop a ternary in:
```tf
resource "aws_db_instance" "foo" {
# ...
snapshot_identifier = "${var.snap}"
name = "${var.snap != "" ? "" : var.dbname}"
}
```
**BUT** the above config will _replace_ the DB on subsequent runs as the
config basically has `name = ""` which will trigger a ForceNew diff once
the `name` is populated from the snapshot restore.
**SO** we can get a workable solution by actively avoiding populating
DBName when we're using one of the engines the docs explicitly mention.
It does not look like there are any tests covering `snapshot_identifer`,
so I'll subject this to some manual tests and follow up with some
results.
* provider/aws: Deprecate roles in favour of role in iam_instance_profile
You can only specify a single role to an IAM Instance Profile. So having
a slice of roles in the provider makes no sense. Therefore, we are going
to deprecate this infavour of `role`
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSIAMInstanceProfile_'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/28 21:24:20 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSIAMInstanceProfile_ -timeout 120m
=== RUN TestAccAWSIAMInstanceProfile_importBasic
--- PASS: TestAccAWSIAMInstanceProfile_importBasic (25.08s)
=== RUN TestAccAWSIAMInstanceProfile_basic
--- PASS: TestAccAWSIAMInstanceProfile_basic (22.40s)
=== RUN TestAccAWSIAMInstanceProfile_withRoleNotRoles
--- PASS: TestAccAWSIAMInstanceProfile_withRoleNotRoles (22.63s)
=== RUN TestAccAWSIAMInstanceProfile_missingRoleThrowsError
--- PASS: TestAccAWSIAMInstanceProfile_missingRoleThrowsError (4.02s)
=== RUN TestAccAWSIAMInstanceProfile_namePrefix
--- PASS: TestAccAWSIAMInstanceProfile_namePrefix (22.18s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 96.349s
```
* Update iam_instance_profile.html.markdown
Fix an issue when upgrading from Terraform < 0.9 to 0.9+, when we added
support for the regional endpoints in OpsWorks Stacks. OpsWorks Stacks
can only be managed via the endpoint with which they were created, not
where the stack resides.
* Adding import to resource_aws_iam_server_certificate.
* provider/aws: Update tests for import of aws_iam_server_certificate
Builds upon the work of @mrcopper in #12940
Resource:
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSIAMServerCertificate_'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/25 00:08:48 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSIAMServerCertificate_ -timeout 120m
=== RUN TestAccAWSIAMServerCertificate_importBasic
--- PASS: TestAccAWSIAMServerCertificate_importBasic (22.81s)
=== RUN TestAccAWSIAMServerCertificate_basic
--- PASS: TestAccAWSIAMServerCertificate_basic (19.68s)
=== RUN TestAccAWSIAMServerCertificate_name_prefix
--- PASS: TestAccAWSIAMServerCertificate_name_prefix (19.88s)
=== RUN TestAccAWSIAMServerCertificate_disappears
--- PASS: TestAccAWSIAMServerCertificate_disappears (13.94s)
=== RUN TestAccAWSIAMServerCertificate_file
--- PASS: TestAccAWSIAMServerCertificate_file (32.67s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 109.062s
```
Data Source:
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSDataSourceIAMServerCertificate_'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/25 13:07:10 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSDataSourceIAMServerCertificate_ -timeout 120m
=== RUN TestAccAWSDataSourceIAMServerCertificate_basic
--- PASS: TestAccAWSDataSourceIAMServerCertificate_basic (43.86s)
=== RUN TestAccAWSDataSourceIAMServerCertificate_matchNamePrefix
--- PASS: TestAccAWSDataSourceIAMServerCertificate_matchNamePrefix (2.68s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 46.569s
```
Updates `aws_caller_identity` data source to actually include the correct attributes from the `GetCallerIdentity` API function.
```
$ make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSCallerIdentity_basic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/27 09:26:13 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSCallerIdentity_basic -timeout 120m
=== RUN TestAccAWSCallerIdentity_basic
--- PASS: TestAccAWSCallerIdentity_basic (12.74s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 12.767s
```
In function `resourceAwsSesReceiptRuleRead` the position of the receipt
rules in the rule set was taken directly from the index of the rule's
position in the slice returned by the AWS API call. As the slice is
zero-based and the ruleset is one-based, this results in an incorrect
representation.
This manifests as `aws_ses_receipt_rule` resources always showing a
diff during plan or apply.
same
Fixes: #13012
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSNetworkAclRule_allProtocol'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/24 18:42:05 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSNetworkAclRule_allProtocol -timeout 120m
=== RUN TestAccAWSNetworkAclRule_allProtocol
--- PASS: TestAccAWSNetworkAclRule_allProtocol (53.95s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 53.974s
```
Fixes: #13035
It was pointed out in the issue that the addition of a new parameter
with a default value AND a ForceNew: true is causing Terraform to try
and recreate the VPC
This PR migrates the state to add the default value of false for `assign_generated_ipv6_cidr_block`
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAWSVpcMigrateState'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/24 12:51:41 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAWSVpcMigrateState -timeout 120m
=== RUN TestAWSVpcMigrateState
2017/03/24 12:52:26 [INFO] Found AWS VPC State v0; migrating to v1
2017/03/24 12:52:26 [DEBUG] Attributes before migration: map[string]string{"assign_generated_ipv6_cidr_block":"true"}
2017/03/24 12:52:26 [DEBUG] Attributes after migration: map[string]string{"assign_generated_ipv6_cidr_block":"false"}
2017/03/24 12:52:26 [INFO] Found AWS VPC State v0; migrating to v1
2017/03/24 12:52:26 [DEBUG] Attributes before migration: map[string]string{}
2017/03/24 12:52:26 [DEBUG] Attributes after migration: map[string]string{"assign_generated_ipv6_cidr_block":"false"}
--- PASS: TestAWSVpcMigrateState (0.00s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 0.024s
```
AWS API requires ECS placement strategies "field" attribute to be
"memory" or "cpu" (lowercase) when type=bin, but these read back as
"MEMORY" and "CPU" (uppercase) respectively.
PR #11565 (which fixed separately reported #11644) deals with this by
always lowering the case of the resource received from the API, but this
breaks for other "field" values (e.g. "instanceId" -> "instanceid").
This PR only lowers the case of the returned resource when field
"MEMORY" or "CPU". Haven't checked if any other fields need this
treatment.
Updates the `data_source_route53_zone` acceptance test to better handle parallel runs. Also better handles tests that potentially leak resources by adding a random integer suffix to domain names.
```
$ make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSRolePolicyAttachment_basic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/22 20:18:05 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSRolePolicyAttachment_basic -timeout 120m
=== RUN TestAccAWSRolePolicyAttachment_basic
--- PASS: TestAccAWSRolePolicyAttachment_basic (31.94s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 31.949s
```
Fixes: #12764
AWS ALB Allows the Subnets to be changed using the SetSubnets func -
previously we set ForceNew: true on this change
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSALB_' ✭
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/18 16:55:52 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSALB_ -timeout 120m
=== RUN TestAccAWSALB_basic
--- PASS: TestAccAWSALB_basic (342.95s)
=== RUN TestAccAWSALB_generatedName
--- PASS: TestAccAWSALB_generatedName (362.05s)
=== RUN TestAccAWSALB_namePrefix
--- PASS: TestAccAWSALB_namePrefix (311.21s)
=== RUN TestAccAWSALB_tags
--- PASS: TestAccAWSALB_tags (344.05s)
=== RUN TestAccAWSALB_updatedSecurityGroups
--- PASS: TestAccAWSALB_updatedSecurityGroups (515.61s)
=== RUN TestAccAWSALB_updatedSubnets
--- PASS: TestAccAWSALB_updatedSubnets (313.94s)
=== RUN TestAccAWSALB_noSecurityGroup
--- PASS: TestAccAWSALB_noSecurityGroup (293.54s)
=== RUN TestAccAWSALB_accesslogs
--- PASS: TestAccAWSALB_accesslogs (492.01s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 2975.402s
```
Fixes: #12895
The AWS API returns both dissociated and associated IPv6 CIDRs. The UI
only returns the associated. Therefore, the assumption was made that we
would always take the 1st association in the set to use for state
We now loop over the set and look for the associated IPv6 CIDR before
using that in state
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSVpc_'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/20 21:21:02 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSVpc_ -timeout 120m
=== RUN TestAccAWSVpc_importBasic
--- PASS: TestAccAWSVpc_importBasic (65.91s)
=== RUN TestAccAWSVpc_basic
--- PASS: TestAccAWSVpc_basic (50.88s)
=== RUN TestAccAWSVpc_enableIpv6
--- PASS: TestAccAWSVpc_enableIpv6 (49.89s)
=== RUN TestAccAWSVpc_dedicatedTenancy
--- PASS: TestAccAWSVpc_dedicatedTenancy (50.59s)
=== RUN TestAccAWSVpc_tags
--- PASS: TestAccAWSVpc_tags (98.89s)
=== RUN TestAccAWSVpc_update
--- PASS: TestAccAWSVpc_update (93.46s)
=== RUN TestAccAWSVpc_bothDnsOptionsSet
--- PASS: TestAccAWSVpc_bothDnsOptionsSet (20.71s)
=== RUN TestAccAWSVpc_DisabledDnsSupport
--- PASS: TestAccAWSVpc_DisabledDnsSupport (49.55s)
=== RUN TestAccAWSVpc_classiclinkOptionSet
--- PASS: TestAccAWSVpc_classiclinkOptionSet (54.92s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 534.829s
```
Leaked resources may prevent this resource from correctly passing acceptance tests. Seeding the policy names with random integer suffixes allows tests to pass regardless of resource leaks.
```
$ make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSRolePolicyAttachment_basic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/22 19:58:58 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSRolePolicyAttachment_basic -timeout 120m
=== RUN TestAccAWSRolePolicyAttachment_basic
--- PASS: TestAccAWSRolePolicyAttachment_basic (31.98s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 31.989s
```
* provider/aws: Increase AMI destroy timeout
Acceptance tests were timing out on AMI destroy, should alleviate the problem.
* Further increase timeout, cleanup test
* use function instead of printf
Updates the IAM Group Policy and IAM User Policy acceptance tests with random integer seeds.
Currently acceptance tests for these two resources are failing from leaked resources, adding distint naming should allow tests to pass regardless of parallel tests being ran or any resource leaks.
```
$ make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSIAMUserPolicy'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/22 00:19:13 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSIAMUserPolicy -timeout 120m
=== RUN TestAccAWSIAMUserPolicy_basic
--- PASS: TestAccAWSIAMUserPolicy_basic (22.54s)
=== RUN TestAccAWSIAMUserPolicy_namePrefix
--- PASS: TestAccAWSIAMUserPolicy_namePrefix (12.49s)
=== RUN TestAccAWSIAMUserPolicy_generatedName
--- PASS: TestAccAWSIAMUserPolicy_generatedName (13.13s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 48.191s
```
```
$ make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSIAMGroupPolicy'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/22 00:24:08 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSIAMGroupPolicy -timeout 120m
=== RUN TestAccAWSIAMGroupPolicy_basic
--- PASS: TestAccAWSIAMGroupPolicy_basic (23.89s)
=== RUN TestAccAWSIAMGroupPolicy_namePrefix
--- PASS: TestAccAWSIAMGroupPolicy_namePrefix (12.07s)
=== RUN TestAccAWSIAMGroupPolicy_generatedName
--- PASS: TestAccAWSIAMGroupPolicy_generatedName (13.15s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 49.140s
```
machines
Fixes: #12898
The way aws_instance works is that we call the Create func then the
Update func then the Read func. The way the work to implement the change
to iam_instance_profile was added meant that when a machine was created
with an iam_instance_profile, it would then try and update that
iam_instance_profile because the state hadn't been updated at that point
We have changed the Update func to only check for the change to
iam_instance_profile when it *is an existing machine* - this will solve
the problem of those bringing up new machines and getting hit with the
permissions error
As requested, added a test that adds an IAM Instance Profile from
creation
```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSInstance_withIamInstanceProfile'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/21 17:51:32 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSInstance_withIamInstanceProfile -timeout 120m
=== RUN TestAccAWSInstance_withIamInstanceProfile
--- PASS: TestAccAWSInstance_withIamInstanceProfile (154.29s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 154.325s
```
Adds support for `name_prefix` to the `aws_autoscaling_group` and `aws_elb` resources. Unfortunately when using `name_prefix` with `aws_elb`, this means that the specified prefix can only be a maximum of 6 characters in length. This is because the maximum length for an ELB name is 32 characters, and `resource.PrefixedUniqueId` generates a 26-character unique identifier. I was considering truncating the unique identifier to allow for a longer `name_prefix`, but I worried that doing so would increase the risk of collisions.
=