Use AWS PrivateLink with Aiven services#

AWS PrivateLink brings Aiven services to the selected virtual private cloud (VPC) in your AWS account. In a traditional setup that uses VPC peering, traffic is routed through an AWS VPC peering connection to your Aiven services. With PrivateLink, you can create a VPC endpoint to your own VPC and access an Aiven service from that. The VPC endpoint creates network interfaces (NIC) to the subnets and availability zones that you choose and receives the private IP addresses that belong to the IP range of your VPC. The VPC endpoint is routed to your Aiven service located in one of Aiven’s AWS accounts.

You can enable PrivateLink for Aiven services located in project VPC. Before you can set up AWS PrivateLink, create a VPC and launch the services that you want to connect to that VPC. As there is no network routing between the VPC, you can use any private IP range for the VPC, unless you also want to connect to the project VPC using VPC peering connections. This means that overlaps in the IP range are not an issue.

You can use either the Aiven web console or the Aiven CLI to set up AWS PrivateLink. You also need the AWS CLI to create a VPC endpoint.

Note: Aiven for Apache Cassandra® and Aiven for M3 services do not currently support AWS PrivateLink.

Create an AWS PrivateLink resource on the Aiven service:

The Amazon Resource Name (ARN) for the principals that are allowed to connect to the VPC endpoint service and the AWS network load balancer requires your Amazon account ID. In addition, you can set the access scope for an entire AWS account, a given user account, or a given role. Only give permissions to roles that you trust, as an allowed role can connect from any VPC.
- Using the Aiven CLI, run the following command including your AWS account ID, the access scope, and the name of your Aiven service:
```
$ avn service privatelink aws create --principal arn:aws:iam::$AWS_account_ID:$access_scope $Aiven_service_name
```
  For example:
```
$ avn service privatelink aws create --principal arn:aws:iam::012345678901:user/mwf my-kafka
```
- Using the Aiven web console:
  1. Log in to the Aiven web console and select the service that you want to use.
  2. Select the Network tab and click Create Privatelink .
  3. Enter the Amazon Resource Names (ARN) for the principals that you want to use, then click Create .
This creates an AWS network load balancer dedicated to your Aiven service and attaches it to an AWS VPC endpoint service that you can later use to connect to your account’s VPC endpoint.

The PrivateLink resource stays in the initial creating state for up to a few minutes while the load balancer is being launched. After the load balancer and VPC endpoint service have been created, the state changes to active and the aws_service_id and aws_service_name values are set.
In the AWS CLI, run the following command to create a VPC endpoint:
```
$ aws ec2 --region eu-west-1 create-vpc-endpoint --vpc-endpoint-type Interface --vpc-id $your_vpc_id --subnet-ids $space_separated_list_of_subnet_ids --security-group-ids $security_group_ids --service-name com.amazonaws.vpce.eu-west-1.vpce-svc-0b16e88f3b706aaf1
```
Replace the --service-name value with the value shown next to Network > AWS service name in the Aiven web console or by running the following command in the Aiven CLI:
```
$ avn service privatelink aws get aws_service_name
```
Note that for fault tolerance, you should specify a subnet ID for each availability zone in the region. The security groups determine the instances that are allowed to connect to the endpoint network interfaces created by AWS into the specified subnets.

Alternatively, you can create the VPC endpoint in the AWS web console under VPC > Endpoints > Create endpoint . See the AWS documentation for details.

Note: For Aiven for Apache Kafka® services, the security group for the VPC endpoint must allow ingress in the port range 10000-31000 to accommodate the pool of Kafka broker ports used in our PrivateLink implementation.

It takes a while before the endpoint is ready to use as AWS provisions network interfaces to each of the subnets and connects them to the Aiven VPC endpoint service. Once the AWS endpoint state changes to available , the connection is visible in Aiven.
Enable PrivateLink access for Aiven service components:

You can control each service component separately - for example, you can enable PrivateLink access for Kafka while allowing Kafka Connect to connect via VPC peering connections only.
- In the Aiven CLI, set user_config.privatelink_access.<service component> to true for the components that you want to enable. For example:
```
$ avn service update -c privatelink_access.kafka=true $Aiven_service_name
$ avn service update -c privatelink_access.kafka_connect=true $Aiven_service_name
$ avn service update -c privatelink_access.kafka_rest=true $Aiven_service_name
$ avn service update -c privatelink_access.schema_registry=true $Aiven_service_name
```
- In the Aiven web console:
  1. Select the Overview tab and scroll down to Advanced configuration .
  2. Click Add configuration , select the component that you want and switch it on.
  3. Click Save advanced configuration .
It takes a couple of minutes before connectivity is available after you enable a service component. This is because AWS requires an AWS load balancer behind each VPC endpoint service, and the target rules on the load balancer for the service nodes need at least two successful heartbeats before they transition from the initial state to healthy and are included in the active forwarding rules of the load balancer.

Note: Currently, you can only create one VPC endpoint for each Aiven service.

Connection information#

Once you have enabled PrivateLink access for a service component, a switch for the privatelink access route appears under Connection information on the Overview tab in the web console. The host - and for some service components such as Kafka, port - values differ from the default dynamic access route that is used to connect to the service. You can use the same credentials with any access route.

Updating the allowed principals list#

To change the list of AWS accounts or IAM users or roles that are allowed to connect a VPC endpoint:

Use the update command of the Aiven CLI:
```
# avn service privatelink aws update --principal arn:aws:iam::$AWS_account_ID:$access_scope $Aiven_service_name
```
Note: When you add an entry, also include the --principal arguments for existing entries.
In the Aiven web console:
1. Select the Network tab and click Edit principals .
2. Enter the principals that you want to include.
3. Click Save .

Deleting a privatelink connection#

Using the Aiven CLI, run the following command:

$ avn service privatelink aws delete $Aiven_service_name

AWS_SERVICE_ID             AWS_SERVICE_NAME                                        PRINCIPALS                         STATE
========================== ======================================================= ================================== ========
vpce-svc-0b16e88f3b706aaf1 com.amazonaws.vpce.eu-west-1.vpce-svc-0b16e88f3b

Using the Aiven web console:
1. Select the Network tab.
2. Click the delete icon on the right of the AWS PrivateLink row.
3. Click Confirm .

This deletes the AWS load balancer and VPC service endpoint.