Amazon ECS Service Connect configuration overview
When you use Service Connect, there are parameters you need to configure in your resources.
The followsing table describes the configuration parameters for the Amazon ECS resources.
Parameter location | App type | Description | Required |
---|---|---|---|
Task definition | Client | There are no changes available for Service Connect in client task definitions. | N/A |
Task definition | Client-server | Servers must add name fields to ports in the portMappings
of containers. For more information, see portMappings |
Yes |
Task definition | Client-server | Servers can optionally provide an application protocol (for example, HTTP) to
receive protocol-specific metrics for their server applications (for example,
HTTP 5xx ). |
No |
Service definition | Client | Client services must add a serviceConnectConfiguration to configure the
namespace to join. This namespace must contain all of the server services that this
service needs to discover. For more information, see serviceConnectConfiguration. |
Yes |
Service definition | Client-server | Server services must add a serviceConnectConfiguration to configure the
DNS names, port numbers, and namespace that the service is available from. For more
information, see serviceConnectConfiguration. |
Yes |
Cluster | Client | Clusters can add a default Service Connect namespace. New services in the cluster inherit the namespace when Service Connect is configured in a service. | No |
Cluster | Client-server | There are no changes available for Service Connect in clusters that apply to server services. Server task definitions and services must set the respective configuration. | N/A |
Overview of steps to configure Service Connect
The following steps provide an overview of how to configure Service Connect.
Important
-
Service Connect creates Amazon Cloud Map services in your account. Modifying these Amazon Cloud Map resources by manually registering/deregistering instances, changing instance attributes, or deleting a service may lead to unexpected behaviour for your application traffic or subsequent deployments.
-
Service Connect doesn't support links in the task definition.
-
Add port names to the port mappings in your task definitions. Additionally, you can identify the layer 7 protocol of the application, to get additional metrics.
-
Create a cluster with a Amazon Cloud Map namespace or create the namespace separately. For simple organization, create a cluster with the name that you want for the namespace and specify the identical name for the namespace. In this case, Amazon ECS creates a new HTTP namespace with the necessary configuration. Service Connect doesn't use or create DNS hosted zones in Amazon Route 53.
-
Configure services to create Service Connect endpoints within the namespace.
-
Deploy services to create the endpoints. Amazon ECS adds a Service Connect proxy container to each task, and creates the Service Connect endpoints in Amazon Cloud Map. This container isn't configured in the task definition, and the task definition can be reused without modification to create multiple services in the same namespace or in multiple namespaces.
-
Deploy client apps as services to connect to the endpoints. Amazon ECS connects them to the Service Connect endpoints through the Service Connect proxy in each task.
Applications only use the proxy to connect to Service Connect endpoints. There is no additional configuration to use the proxy. The proxy performs round-robin load balancing, outlier detection, and retries. For more information about the proxy, see Service Connect proxy.
-
Monitor traffic through the Service Connect proxy in Amazon CloudWatch.
Cluster configuration
You can set a default namespace for Service Connect when you create or update the cluster. If you specify a namespace name that doesn't exist in the same Amazon Web Services Region and account, a new HTTP namespace is created.
If you create a cluster and specify a default Service Connect namespace, the cluster waits in
the PROVISIONING
status while Amazon ECS creates the namespace. You can see an
attachment
in the status of the cluster that shows the status of the namespace.
Attachments aren't displayed by default in the Amazon CLI, you must add --include
ATTACHMENTS
to see them.
Service configuration
Service Connect is designed to require the minimum configuration. You need to set a name for
each port mapping that you would like to use with Service Connect in the task definition. In the
service, you need to turn on Service Connect and select a namespace to make a client service. To
make a client-server service, you need to add a single Service Connect service configuration that
matches the name of one of the port mappings. Amazon ECS reuses the port number and port name from the
task definition to define the Service Connect service and endpoint. To override those values, you
can use the other parameters Discovery, DNS, and
Port in the console, or discoveryName
and
clientAliases
, respectively in the Amazon ECS API.