mirror of https://github.com/hashicorp/consul
100 lines
3.7 KiB
Markdown
100 lines
3.7 KiB
Markdown
---
|
|
layout: docs
|
|
page_title: Migrate existing tasks to Consul service mesh
|
|
description: >-
|
|
You can migrate tasks in existing Amazon Web Services ECS deployments to a service mesh deployed with Terraform. Learn how to convert a task specified as an ECS task definition into a `mesh-task` Terraform module.
|
|
---
|
|
|
|
# Migrate existing tasks to Consul on ECS with Terraform
|
|
|
|
To migrate existing tasks to Consul, rewrite the existing Terraform code for your tasks so that the container definitions include the [`mesh-task` Terraform module](https://registry.terraform.io/modules/hashicorp/consul-ecs/aws/latest/submodules/mesh-task).
|
|
|
|
Your tasks must already be defined in Terraform using the `ecs_task_definition` resource so that they can then be converted to use the `mesh-task` module.
|
|
|
|
## Example
|
|
|
|
The following example shows an existing task definition configured in Terraform:
|
|
|
|
```hcl
|
|
resource "aws_ecs_task_definition" "my_task" {
|
|
family = "my_task"
|
|
requires_compatibilities = ["FARGATE"]
|
|
network_mode = "awsvpc"
|
|
cpu = 256
|
|
memory = 512
|
|
execution_role_arn = "arn:aws:iam::111111111111:role/execution-role"
|
|
task_role_arn = "arn:aws:iam::111111111111:role/task-role"
|
|
container_definitions = jsonencode(
|
|
[{
|
|
name = "example-client-app"
|
|
image = "docker.io/org/my_task:v0.0.1"
|
|
essential = true
|
|
portMappings = [
|
|
{
|
|
containerPort = 9090
|
|
hostPort = 9090
|
|
protocol = "tcp"
|
|
}
|
|
]
|
|
cpu = 0
|
|
mountPoints = []
|
|
volumesFrom = []
|
|
}]
|
|
)
|
|
}
|
|
|
|
resource "aws_ecs_service" "my_task" {
|
|
name = "my_task"
|
|
cluster = "arn:aws:ecs:us-east-1:111111111111:cluster/my-cluster"
|
|
task_definition = aws_ecs_task_definition.my_task.arn
|
|
desired_count = 1
|
|
network_configuration {
|
|
subnets = ["subnet-abc123"]
|
|
}
|
|
launch_type = "FARGATE"
|
|
}
|
|
```
|
|
|
|
|
|
Replace the `aws_ecs_task_definition` resource with the `mesh-task` module so that Consul adds the necessary dataplane containers that enable your task to join the mesh. The `mesh-task` module uses inputs similar to your old ECS task definition but creates a new version of the task definition with additional containers.
|
|
|
|
The following Terraform configuration uses the `mesh-task` module to replace the previous example's task definition:
|
|
|
|
```hcl
|
|
module "my_task" {
|
|
source = "hashicorp/consul-ecs/aws//modules/mesh-task"
|
|
version = "<latest version>"
|
|
|
|
family = "my_task"
|
|
container_definitions = [
|
|
{
|
|
name = "example-client-app"
|
|
image = "docker.io/org/my_task:v0.0.1"
|
|
essential = true
|
|
portMappings = [
|
|
{
|
|
containerPort = 9090
|
|
hostPort = 9090
|
|
protocol = "tcp"
|
|
}
|
|
]
|
|
cpu = 0
|
|
mountPoints = []
|
|
volumesFrom = []
|
|
}
|
|
]
|
|
|
|
port = 9090
|
|
consul_server_hosts = "<address of the Consul server>"
|
|
}
|
|
|
|
```
|
|
|
|
Note the following differences:
|
|
|
|
- The `execution_role_arn` and `task_role_arn` fields are removed. The `mesh-task` module creates the task and execution roles by default. If you need to use existing IAM roles, set the `task_role` and `execution_role` fields to pass in existing roles.
|
|
- The `port` field specifies the port that your application listens on. If your application has no listening port, set `outbound_only = true` and remove the `port` field.
|
|
- The `jsonencode()` function is removed from the `container_definitions` field.
|
|
|
|
The `mesh-task` module creates a new version of your task definition with the necessary dataplane containers so you can delete your existing `aws_ecs_task_definition` resource.
|