Database Access with Amazon Redshift Serverless

Teleport can provide secure access to Amazon Redshift Serverless via the Teleport Database Service. This allows for fine-grained access control through Teleport's RBAC.

In this guide, you will:

1. Configure your Amazon Redshift Serverless database with IAM authentication.
2. Add the database to your Teleport cluster.
3. Connect to the database via Teleport.

This guide will help you to:

• Set up Teleport to access your Amazon Redshift Serverless workgroups.
• Connect to your databases through Teleport.

How it works

The Teleport Database Service uses IAM authentication to communicate with Redshift Serverless. When a user connects to the database via Teleport, the Teleport Database Service obtains AWS credentials and authenticates to AWS as an IAM principal with permissions to access the database.

• Self-Hosted
• Teleport Enterprise Cloud

This guide shows how to register a single Amazon Redshift Serverless database with your Teleport cluster. For a more scalable approach, learn how to set up Database Auto-Discovery to automatically enroll all AWS databases in your infrastructure.

Prerequisites

• A running Teleport cluster version 16.4.8 or above. If you want to get started with Teleport, sign up for a free trial or set up a demo environment.

• The tctl admin tool and tsh client tool.

  Visit Installation for instructions on downloading tctl and tsh.

• AWS account with a Redshift Serverless configuration and permissions to create and attach IAM policies.
• Command-line client psql installed and added to your system's PATH environment variable.
• A host where you will run the Teleport Database Service. This guide assumes an EC2 instance, and provides a corresponding example of access control.
• To check that you can connect to your Teleport cluster, sign in with tsh login, then verify that you can run tctl commands using your current credentials. For example:

  tsh login --proxy=teleport.example.com --user=[email protected]
  tctl status
  Cluster  teleport.example.com
  Version  16.4.8
  CA pin   sha256:abdc1245efgh5678abdc1245efgh5678abdc1245efgh5678abdc1245efgh5678

  If you can connect to the cluster and run the tctl status command, you can use your current credentials to run subsequent tctl commands from your workstation. If you host your own Teleport cluster, you can also run tctl commands on the computer that hosts the Teleport Auth Service for full permissions.

Step 1/5. Create an IAM Role for user access

Create an AWS IAM role to provide user access to Redshift Serverless. This role will be granted to Teleport users via a corresponding Teleport role. In this guide we will give this role the name teleport-redshift-serverless-access.

Configure the role's trust policy to trust the AWS account. This will be sufficient to allow the Teleport Database Service to assume the role, which we'll be setting up in the next step:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "Statement1",
            "Effect": "Allow",
            "Principal": {
                "AWS": "arn:aws:iam::aws-account-id:root"
            },
            "Action": "sts:AssumeRole"
        }
    ]
}

Remember to replace the example AWS account ID.

Attach a permission policy to the role to allow it to connect to Redshift Serverless databases:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "redshift-serverless:GetCredentials",
            "Resource": "*"
        }
    ]
}

The resource ARN string has the following format and can be more specific if you only want to allow access to specific work groups:

arn:aws:redshift-serverless:{Region}:{AccountID}:workgroup/{WorkgroupID}

See Identity and access management in Amazon Redshift Serverless for more information about configuring Redshift Serverless permissions.

Step 2/5. Configure Database Service IAM permissions

The Teleport Database Service needs AWS IAM permissions to provide access to Redshift Serverless databases.

Create an IAM role for Teleport

Grant the Database Service access to credentials that it can use to authenticate to AWS.

• If you are running the Database Service on an EC2 instance, you may use the EC2 Instance Metadata Service method
• If you are running the Database Service in Kubernetes, you can use IAM Roles for Service Accounts (IRSA)
• Otherwise, you must use environment variables

AWS_ACCESS_KEY_ID=00000000000000000000
AWS_SECRET_ACCESS_KEY=0000000000000000000000000000000000000000
AWS_DEFAULT_REGION=<YOUR_REGION>

Grant permissions

Attach the following AWS IAM permissions to the Database Service IAM role:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "RedshiftServerlessConnectAsIAMRole",
            "Effect": "Allow",
            "Action": "sts:AssumeRole",
            "Resource": [
                "arn:aws:iam::aws-account-id:role/teleport-redshift-serverless-access"
            ]
        },
        {
            "Sid": "RedshiftServerlessFetchMetadata",
            "Effect": "Allow",
            "Action": [
                "redshift-serverless:GetEndpointAccess",
                "redshift-serverless:GetWorkgroup"
            ],
            "Resource": "*"
        }
    ]
}

Databases discovered by the Teleport Discovery Service should be registered with complete metadata, so you can also omit the RedshiftServerlessFetchMetadata permissions if all of your AWS databases are being auto-discovered.

Redshift Serverless maps IAM roles to database users. The Teleport Database Service must be able to assume these "access" IAM roles which are granted IAM permissions to generate IAM authentication tokens.

Step 3/5. Deploy a Database Service

The Teleport Database Service needs network connectivity to the Redshift Serverless endpoint and to your Teleport cluster.

If you are deploying it in AWS, make sure that its deployed in a subnet with the necessary routes and make sure that its security group(s) allow the outbound traffic.

Also, ensure that the security group(s) attached to your Redshift Serverless workgroup allows inbound traffic from the Teleport Database Service host.

Install Teleport

Install Teleport on your Linux server:

1. Assign edition to one of the following, depending on your Teleport edition:

   Edition	Value
   Teleport Enterprise Cloud	cloud
   Teleport Enterprise (Self-Hosted)	enterprise
   Teleport Community Edition	oss

2. Get the version of Teleport to install. If you have automatic agent updates enabled in your cluster, query the latest Teleport version that is compatible with the updater:

   TELEPORT_DOMAIN=example.teleport.com
   TELEPORT_VERSION="$(curl https://$TELEPORT_DOMAIN/v1/webapi/automaticupgrades/channel/default/version | sed 's/v//')"

   Otherwise, get the version of your Teleport cluster:

   TELEPORT_DOMAIN=example.teleport.com
   TELEPORT_VERSION="$(curl https://$TELEPORT_DOMAIN/v1/webapi/ping | jq -r '.server_version')"

3. Install Teleport on your Linux server:

   curl https://cdn.teleport.dev/install-v16.4.8.sh | bash -s ${TELEPORT_VERSION} edition

   The installation script detects the package manager on your Linux server and uses it to install Teleport binaries. To customize your installation, learn about the Teleport package repositories in the installation guide.

Generate a config file

Update REDSHIFT_SERVERLESS_URI to the domain name and port of the cluster. On the node that is running the Database Service, create a configuration file:

sudo teleport db configure create \   -o file \   --name="redshift-serverless" \   --proxy=teleport.example.com:3080 \   --protocol=postgres \   --uri=REDSHIFT_SERVERLESS_URI \   --token=/tmp/token

sudo teleport db configure create \   -o file \   --name="redshift-serverless" \   --proxy=example.teleport.sh:443  \   --protocol=postgres \   --uri=REDSHIFT_SERVERLESS_URI \   --token=/tmp/token

The command will generate a Database Service configuration to proxy your AWS Redshift Serverless instance and place it at the /etc/teleport.yaml location.

Create a join token

The Database Service requires a valid join token to join your Teleport cluster. Run the following tctl command and save the token output in /tmp/token on the server that will run the Database Service:

tctl tokens add --type=db --format=text
abcd123-insecure-do-not-use-this

Start the Database service

Configure the Database Service to start automatically when the host boots up by creating a systemd service for it. The instructions depend on how you installed the Database Service.

sudo systemctl enable teleport
sudo systemctl start teleport

sudo teleport install systemd -o /etc/systemd/system/teleport.service
sudo systemctl enable teleport
sudo systemctl start teleport

You can check the status of the Database Service with systemctl status teleport and view its logs with journalctl -fu teleport.

Step 4/5. Create a Teleport role

On your workstation logged in to your Teleport cluster with tsh, define a new role to provide access to Redshift Serverless. Our example file is redshift-role.yaml:

version: v5
kind: role
metadata:
  name: redshift-serverless-access
spec:
  allow:
    db_labels:
      '*': '*'
    db_names:
    - dev
    db_users:
    - 'teleport-redshift-serverless-access'

• The value of db_users corresponds to the IAM role created in the previous step. You can provide either the role name or the full AWS ARN of the IAM role.
• The value(s) for db_names will depend on your Redshift Serverless configuration, but dev is the default name applied by AWS. You can also provide * to grant access to all instances.

Save this file and apply it to your Teleport cluster:

tctl create -f redshift-role.yaml
role 'redshift-serverless-access' has been created

Assign the redshift-serverless-access role to your Teleport user by running the appropriate commands for your authentication provider:

Step 5/5. Connect

Once the Database Service has started and joined the cluster, log in to see the registered databases. Replace --proxy with the address of your Teleport Proxy Service or cloud tenant:

tsh login --proxy=mytenant.teleport.sh --user=alice
tsh db ls
Name        Description                    Labels----------- ------------------------------ --------my-redshift                                ...

To connect to the Redshift Serverless instance:

tsh db connect my-redshift --db-user=teleport-redshift-serverless-access --db-name=dev
psql (15.1, server 8.0.2)WARNING: psql major version 15, server major version 8.0.         Some psql features might not work.SSL connection (protocol: TLSv1.3, cipher: TLS_CHACHA20_POLY1305_SHA256, compression: off)Type "help" for help.
dev=>

To log out of the database and remove credentials:

tsh db logout my-redshift

Troubleshooting

User permission errors

The IAM role teleport-redshift-serverless-access will be automatically mapped as IAMR:teleport-redshift-serverless-access inside the Redshift Serverless database.

Users (database admins) can optionally set up this database user's permissions prior to logging in as this new IAM role to avoid or resolve user permission issues:

1. Connect to the Redshift Serverless workgroup as the admin user, and execute:

   CREATE USER "IAMR:teleport-redshift-serverless-access" WITH PASSWORD DISABLE;
   

2. Grant this user appropriate in-database permissions. For example:

   GRANT SELECT ON TABLE users TO "IAMR:teleport-redshift-serverless-access";
   

Certificate error

If your tsh db connect error includes the following text, you likely have an RDS or DocumentDB database created before July 28, 2020, which presents an X.509 certificate that is incompatible with Teleport:

x509: certificate relies on legacy Common Name field, use SANs instead

AWS provides instructions to rotate your SSL/TLS certificate.

No credential providers error

If you see the error NoCredentialProviders: no valid providers in chain in Database Service logs then Teleport is not detecting the required credentials to connect via AWS IAM permissions. Check whether the credentials or security role has been applied in the machine running the Teleport Database Service.

When running on EKS, this error may occur if the Teleport Database Service cannot access IMDSv2 when the PUT requests hop limit on the worker node instance is set to 1. You can use the following commands to check the hop limit:

aws ec2 describe-instances --instance-ids <node-instance-id> | grep HttpPutResponseHopLimit
                        "HttpPutResponseHopLimit": 1,

See IMDSv2 support for EKS and EKS best practices for more details.

Timeout errors

The Teleport Database Service needs connectivity to your database endpoints. That may require enabling inbound traffic on the database from the Database Service on the same VPC or routing rules from another VPC. Using the nc program you can verify connections to databases:

nc -zv postgres-instance-1.sadas.us-east-1.rds.amazonaws.com 5432
Connection to postgres-instance-1.sadas.us-east-1.rds.amazonaws.com (172.31.24.172) 5432 port [tcp/postgresql] succeeded!

Not authorized to perform sts:AssumeRole

The Database Service assumes an IAM role in one of following situations:

• A Teleport user specifies an IAM role as the database user they wish to use when accessing AWS services that require IAM roles as database users. Databases that support using an IAM role as a database user include: DynamoDB, Keyspaces, Opensearch, Redshift, and Redshift Serverless.
• The assume_role_arn field is specified for the database resources or dynamic resource matchers.

You may encounter the following error if the trust relationship is not configured properly between the IAM roles:

AccessDenied: User: arn:aws:sts::111111111111:assumed-role/teleport-db-service-role/i-* is not authorized to perform: sts:AssumeRole on resource: arn:aws:iam::111111111111:role/db-user-role

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::aws-account-id:role/teleport-db-service-role"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::aws-account-id:root"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::external-aws-account-id:role/teleport-db-service-role"
      },
      "Action": "sts:AssumeRole",
      "Condition": {
        "StringEquals": {
          "sts:ExternalId": "example-external-id"
        }
      }
    }
  ]
}

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": "sts:AssumeRole",
            "Effect": "Allow",
            "Resource": "arn:aws:iam::aws-account-id:role/db-user-role"
        }
    ]
}

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": "sts:AssumeRole",
            "Effect": "Allow",
            "Resource": "*"
        }
    ]
}

You can test the trust relationship by running this AWS CLI command as teleport-db-service-role:

aws sts assume-role --role-arn arn:aws:iam::111111111111:role/db-user-role --role-session-name test-trust-relationship

Learn more on how to use trust policies with IAM roles.

Unable to cancel a query

If you use a PostgreSQL cli client like psql, and you try to cancel a query with ctrl+c, but it doesn't cancel the query, then you need to connect using a tsh local proxy instead. When psql cancels a query, it establishes a new connection without TLS certificates, however Teleport requires TLS certificates not only for authentication, but also to route database connections.

If you enable TLS Routing in Teleport then tsh db connect will automatically start a local proxy for every connection. Alternatively, you can connect via Teleport Connect which also uses a local proxy. Otherwise, you need to start a tsh local proxy manually using tsh proxy db and connect via the local proxy.

If you have already started a long-running query in a psql session that you cannot cancel with ctrl+c, you can start a new client session to cancel that query manually:

First, find the query's process identifier (PID):

SELECT session_id AS pid, database_name,start_time,trim(query_text) AS query FROM SYS_QUERY_HISTORY WHERE status = 'running';

Next, gracefully cancel the query using its PID. This will send a SIGINT signal to the postgres backend process for that query:

SELECT pg_cancel_backend(<PID>);

You should always try to gracefully terminate a query first, but if graceful cancellation is taking too long, then you can forcefully terminate the query instead. This will send a SIGTERM signal to the postgres backend process for that query:

SELECT pg_terminate_backend(<PID>);

See the PostgreSQL documentation on admin functions for more information about the pg_cancel_backend and pg_terminate_backend functions.

Next steps

• Learn more about using IAM authentication to generate database user credentials for Amazon Redshift.
• Learn how to restrict access to certain users and databases.
• View the High Availability (HA) guide.
• Take a look at the YAML configuration reference.