Joining Services via AWS IAM Role
This guide explains how to use the IAM join method to configure Teleport processes to join your Teleport cluster without sharing any secrets when they are running in AWS.
There are two other AWS join methods available depending on your use case:
- The EC2 join method, which is only available for self-hosted Teleport deployments (see documentation). A Teleport process running on an EC2 instance requests a signed EC2 instance identity document and presents it to the Teleport Auth Service, which queries the EC2 API to verify that the instance is genuine. This method requires a self-hosted Teleport cluster and IAM credentials for the Teleport Auth Service.
- Tokens not signed by AWS: You can configure Teleport processes running on AWS to join a cluster via Teleport join tokens or, for Teleport processes running on Kubernetes, signed ServiceAccount tokens. These approaches allow you to join a Teleport process to a cluster when you don't want to rely on AWS-specific APIs, e.g., when adopting a cloud-agnostic approach.
How it works
The IAM join method is available to any Teleport process running anywhere with access to IAM credentials, such as an EC2 instance with an attached IAM role. No specific permissions or IAM policy is required: an IAM role with no attached policies is sufficient. No IAM credentials are required on the Teleport Auth Service.
Teleport processes prove that they are running in your AWS account by sending a
pre-signed sts:GetCallerIdentity
request to the Teleport Auth Service. The
service's identity must match an allow rule configured in your AWS service
joining token.
Support for joining a cluster with the Proxy Service behind a layer 7 load balancer or reverse proxy is available in Teleport 13.0+.
Prerequisites
-
A running Teleport cluster version 14.3.33 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 andtsh
client tool.Visit Installation for instructions on downloading
tctl
andtsh
.
- An AWS EC2 instance to host a Teleport service, with the Teleport binary installed.
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 14.3.33
# 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 1/4. Set up AWS IAM credentials
Every Teleport process using the IAM method to join your Teleport cluster needs
AWS IAM credentials in order to call the sts:GetCallerIdentity
API. No
specific IAM policy or permissions are needed. Any IAM user or role can call
this API.
If running Teleport on an EC2 instance, it is sufficient to attach any IAM role
to the instance. To attach an IAM role from the EC2 dashboard, select Actions > Security > Modify IAM role
. It is not necessary for the role to have any
attached IAM policies at all. If your instance does not otherwise need AWS
credentials, it is preferred to create and attach an empty role with no attached
policies.
Step 2/4. Create the AWS joining token
Create the following token.yaml
with an allow
rule specifying your AWS
account and the ARN that the Teleport process's identity must match.
# token.yaml
kind: token
version: v2
metadata:
# the token name is not a secret because instances must prove that they are
# running in your AWS account to use this token
name: iam-token
spec:
# use the minimal set of roles required (e.g. Node, App, Kube, DB, WindowsDesktop)
roles: [Node]
# set the join method allowed for this token
join_method: iam
allow:
# specify the AWS account which Teleport processes may join from
- aws_account: "111111111111"
# multiple allow rules are supported
- aws_account: "222222222222"
# aws_arn is optional and allows you to restrict the IAM role of joining
# Teleport processes
- aws_account: "333333333333"
aws_arn: "arn:aws:sts::333333333333:assumed-role/teleport-node-role/i-*"
The token name iam-token
is just an example and can be any value you want to
use, as long as you use the same value for join_params.token_name
in Step 3.
The optional aws_arn
field in the allow rules supports wildcard characters:
*
to match any combination of characters?
to match any single character
Run the following command to create the token:
$ tctl create -f token.yaml
Step 3/4. Configure your services
The IAM join method can be used for Teleport processes running the SSH, Proxy, Kubernetes, Application, or Database Service.
Configure your Teleport service with a custom teleport.yaml
file. Use the
join_params
section with token_name
matching your token created in Step 2
and method: iam
as shown in the following example config:
# /etc/teleport.yaml
version: v3
teleport:
join_params:
token_name: iam-token
method: iam
proxy_server: teleport.example.com:443
ssh_service:
enabled: yes
auth_service:
enabled: no
proxy_service:
enabled: no
In the teleport.proxy_server
field, replace the value with the host and web
port of your Teleport Proxy Service or Teleport Enterprise Cloud tenant, e.g.,
mytenant.teleport.sh:443
.
Step 4/4. Launch your Teleport process
Grant your Teleport instance access to credentials that it can use to authenticate to AWS. If you are running your Teleport instance on an EC2 instance, you should use the EC2 Instance Metadata Service method. Otherwise, you must use environment variables:
- Instance Metadata Service
- Environment Variables
Teleport will detect when it is running on an EC2 instance and use the Instance Metadata Service to fetch credentials.
The EC2 instance should be configured to use an EC2 instance profile. For more information, see: Using Instance Profiles.
Teleport's built-in AWS client reads credentials from the following environment variables:
AWS_ACCESS_KEY_ID
AWS_SECRET_ACCESS_KEY
AWS_DEFAULT_REGION
When you start your Teleport instance, the service reads environment variables from a
file at the path /etc/default/teleport
. Obtain these credentials from your
organization. Ensure that /etc/default/teleport
has the following content,
replacing the values of each variable:
AWS_ACCESS_KEY_ID=00000000000000000000
AWS_SECRET_ACCESS_KEY=0000000000000000000000000000000000000000
AWS_DEFAULT_REGION=<YOUR_REGION>
Have multiple sources of AWS credentials?
Teleport's AWS client loads credentials from different sources in the following order:
- Environment Variables
- Shared credentials file
- Shared configuration file (Teleport always enables shared configuration)
- EC2 Instance Metadata (credentials only)
While you can provide AWS credentials via a shared credentials file or shared
configuration file, you will need to run your Teleport instance with the AWS_PROFILE
environment variable assigned to the name of your profile of choice.
If you have a specific use case that the instructions above do not account for, consult the documentation for the AWS SDK for Go for a detailed description of credential loading behavior.
Configure your Teleport instance to start automatically when the host boots up by creating a systemd service for it. The instructions depend on how you installed your Teleport instance.
- Package Manager
- TAR Archive
On the host where you will run your Teleport instance, enable and start Teleport:
$ sudo systemctl enable teleport
$ sudo systemctl start teleport
On the host where you will run your Teleport instance, create a systemd service configuration for Teleport, enable the Teleport service, and 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 your Teleport instance with systemctl status teleport
and view its logs with journalctl -fu teleport
.
Once you have started Teleport, confirm that your service is able to connect to and join your cluster.