Database Access with Redshift on AWS

Teleport can provide secure access to Amazon Redshift 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 database with IAM authentication.
2. Add the database to your Teleport cluster.
3. Connect to the database via Teleport.

How it works

The Teleport Database Service uses IAM authentication to communicate with Amazon Redshift. 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 manage the database.

• Self-Hosted
• Teleport Enterprise Cloud

This guide shows how to register a single Amazon Redshift cluster 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 15.4.22 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.

  On Teleport Enterprise, you must use the Enterprise version of tctl, which you can download from your Teleport account workspace. Otherwise, visit Installation for instructions on downloading tctl and tsh for Teleport Community Edition.

• AWS account with a Redshift cluster and permissions to create and attach IAM policies.
• Command-line client psql installed and added to your system's PATH environment variable.
• A host, e.g., an EC2 instance, where you will run the Teleport Database Service.
• 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. tctl is supported on macOS and Linux machines. For example:

  tsh login --proxy=teleport.example.com --user=email@example.com
  tctl status
  Cluster  teleport.example.com
  Version  15.4.22
  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 1/6. Create a Teleport user

tctl users add \  --roles=access \  --db-users="*" \  --db-names="*" \  alice

tctl users add \  --roles=access,requester \  --db-users="*" \  --db-names="*" \  alice

For more detailed information about database access controls and how to restrict access see RBAC documentation.

Step 2/6. Create a Database Service configuration

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

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-v15.4.22.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.

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

sudo teleport db configure create \   -o file \   --name="redshift-postgres" \   --proxy=teleport.example.com:3080 \   --protocol=postgres \   --token=/tmp/token \   --uri=${CLUSTER_URI?}

sudo teleport db configure create \   -o file \   --name="redshift-postgres" \   --proxy=mytenant.teleport.sh:443 \   --protocol=postgres \   --token=/tmp/token \   --uri=${CLUSTER_URI?}

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

Step 3/6. Create an IAM Role for user access (optional)

Redshift supports two methods of IAM authentication, both of which Teleport also supports.

First is IAM authentication as a database user. In this method, the Teleport Database Service generates a temporary IAM authentication token for a database user that already exists in the Redshift database. If you choose to use this method, you can skip this step as no additional IAM roles are required.

The second method is to authenticate as an IAM role. In this case, the Teleport Database Service assumes an IAM role to authenticate with Redshift. Redshift then maps that IAM role to a database username and creates that database user if it doesn't already exist in the database.

If you choose the second method, create the AWS IAM role to provide user access to the Redshift database. Go to IAM -> Access Management -> Roles, and click "Create Role".

Skip "Add permissions" for now, enter a role name, and press "Create role".

Once the role is created, find the role, and add the following inline policy to the IAM role:

Or in JSON format:

{
	"Version": "2012-10-17",
	"Statement": [
		{
			"Effect": "Allow",
			"Action": "redshift:GetClusterCredentialsWithIAM",
			"Resource": "arn:aws:redshift:us-east-1:123456789012:dbname:my-redshift/*"
		}
	]
}

Replace 123456789012 and my-redshift with your AWS account ID and your Redshift database's cluster ID.

Step 4/6. Create an IAM policy for the Database Service

Teleport needs AWS IAM permissions to be able to:

• Manage IAM user or IAM role policies, for IAM authentication as database users.
• Assume IAM roles, for IAM authentication as IAM roles.

Before you can generate IAM permissions, you must provide the Teleport Database Service access to AWS credentials.

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. Otherwise, you must use environment variables:

AWS_ACCESS_KEY_ID=00000000000000000000
AWS_SECRET_ACCESS_KEY=0000000000000000000000000000000000000000
AWS_DEFAULT_REGION=<YOUR_REGION>

Teleport can bootstrap IAM permissions for the Database Service based on its configuration using the teleport db configure bootstrap command. You can use this command in automatic or manual mode:

• In automatic mode, Teleport will attempt to create appropriate IAM policies and attach them to the specified IAM identity role. This requires IAM permissions to create and attach IAM policies.
• In manual mode, Teleport will print required IAM policies. You can then create and attach them manually using the AWS management console.

teleport db configure bootstrap -c /etc/teleport.yaml --attach-to-role TeleportRole

teleport db configure bootstrap -c /etc/teleport.yaml --manual --attach-to-role arn:aws:iam::123456789012:role/TeleportRole

Step 5/6. 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.

The Database Service will proxy the Amazon Redshift cluster with the ID you specified earlier. Keep in mind that AWS IAM changes may not propagate immediately and can take a few minutes to come into effect.

Step 6/6. Connect

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

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

To retrieve credentials for a database and connect to it:

tsh db connect --db-user=alice --db-name=dev my-redshift

tsh db connect --db-user=role/my-iam-role --db-name=dev my-redshift

To log out of the database and remove credentials:

tsh db logout my-redshift

Troubleshooting

Certificate error

If your tsh db connect error includes the following text, you likely have an RDS 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:

• An IAM role is used as db_user when accessing AWS services that require IAM roles as database users, such as DynamoDB, Keyspaces, Opensearch, 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/database-service-role/i-* is not authorized to perform: sts:AssumeRole on resource: arn:aws:iam::111111111111:role/database-user-role

To allow IAM Role role1 to assume IAM Role role2, the following is generally required:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::aws-account-id:role/role1"
      },
      "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/role1"
      },
      "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/role2"
        }
    ]
}

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

You can test the trust relationship by running this AWS CLI command as role1:

aws sts assume-role --role-arn arn:aws:iam::111111111111:role/role2 --role-session-name test-trust-relationship

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

Maximum policy size exceeded errors

Due to IAM and STS character limits, you may encounter one of the following errors in the Database Service logs when large numbers of databases are registered:

• LimitExceeded: Maximum policy size of 2048 bytes exceeded for user <iam-user>
• LimitExceeded: Maximum policy size of 10240 bytes exceeded for role <iam-role>

For reference, a user policy can maintain permissions for approximately 6 Redshift databases, or 20 RDS databases due to the IAM policy character limits. A role policy can maintain permissions for approximately 30 Redshift databases, or 100 RDS databases.

To get around this limit, try using one or a combination of the following methods:

discovery_service:
  enabled: "yes"
  aws:
    - types: ["rds"]
      regions: ["us-west-1", "us-west-2"]
      assume_role_arn: "arn:aws:iam::123456789012:role/example-role-rds-env-prod-discovery"
      tags:
        "env": "prod"

    - types: ["redshift", "redshift-serverless"]
      regions: ["us-west-2"]
      assume_role_arn: "arn:aws:iam::123456789012:role/example-role-redshift-env-dev"
      tags:
        "env": "dev"

db_service:
  enabled: "yes"
  resources:
    # Matches us-west-1 env=prod RDS databases from Discovery Service, and
    # overwrites assume_role_arn.
    - labels:
        "env": "prod"
        "region": "us-west-1"
      aws:
        assume_role_arn: "arn:aws:iam::123456789012:role/example-role-rds-env-prod-us-west-1-access"

    # Matches us-west-2 env=prod RDS databases from Discovery Service, and
    # overwrites assume_role_arn.
    - labels:
        "env": "prod"
        "region": "us-west-2"
      aws:
        assume_role_arn: "arn:aws:iam::123456789012:role/example-role-rds-env-prod-us-west-2-access"

    # Matches env=dev Redshift databases from Discovery Service and inherits
    # "arn:aws:iam::123456789012:role/example-role-redshift-env-dev"
    - labels:
        "env": "dev"

teleport db configure aws create-iam --types redshift,redshift-serverless --name teleport-redshift-access
teleport db configure aws print-iam --types redshift,redshift-serverless

db_service:
  enabled: "yes"
  aws:
    - types: ["rds"]
      regions: ["us-west-1", "us-west-2"]
      assume_role_arn: "arn:aws:iam::123456789012:role/example-role-rds-env-prod"
      tags:
        "env": "prod"

    - types: ["redshift", "redshift-serverless"]
      regions: ["us-west-2"]
      assume_role_arn: "arn:aws:iam::123456789012:role/example-role-redshift-env-dev"
      tags:
        "env": "dev"

teleport db configure bootstrap \    -c /etc/teleport.yaml \    --policy-name teleport-policy-rds-env-prod \    --attach-to-role "arn:aws:iam::123456789012:role/example-role-rds-env-prod"

db_service:
  enabled: "yes"
  databases:
  - name: "rds-postgres"
    protocol: "postgres"
    uri: "rds-postgres.abcdef012345.us-west-1.rds.amazonaws.com:5432"
    aws:
        assume_role_arn: "arn:aws:iam::123456789012:role/example-rds-access-role"

teleport db configure bootstrap \    -c /etc/teleport.yaml \    --policy-name teleport-policy-rds-access \    --attach-to-role "arn:aws:iam::123456789012:role/example-rds-access-role"

kind: db
version: v3
metadata:
  name: "rds-postgres"
  labels:
    env: "dev"
spec:
  protocol: "postgres"
  uri: "rds-postgres.abcdef012345.us-west-1.rds.amazonaws.com:5432"
  aws:
    assume_role_arn: "arn:aws:iam::123456789012:role/example-rds-access-role"

db_service:
  enabled: "yes"
  resources:
    # Matches env=dev databases and overwrites assume_role_arn.
    - labels:
        "env": "dev"
      aws:
        assume_role_arn: "arn:aws:iam::123456789012:role/example-env-dev-access"

    # Matches env=prod database, and use the assume_role_arn in the database's
    # definition or use the host IAM identity if assume_role_arn is empty.
    - labels:
        "env": "prod"

teleport db configure aws create-iam --types rds --name teleport-rds-access
teleport db configure aws print-iam --types rds

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "rds-db:connect",
            "Resource": "*"
        }
    ]
}

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

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 pid,starttime,duration,trim(user_name) AS user,trim(query) AS query FROM stv_recents 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.

SSL SYSCALL error

You may encounter the following error when your local psql is not compatible with newer versions of OpenSSL:

tsh db connect --db-user postgres --db-name postgres postgres
psql: error: connection to server at "localhost" (::1), port 12345 failed: Connection refused    Is the server running on that host and accepting TCP/IP connections?connection to server at "localhost" (127.0.0.1), port 12345 failed: SSL SYSCALL error: Undefined error: 0

Please upgrade your local psql to the latest version.

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.