FAQ

Q: Does Atlantis affect Terraform remote state?

A: No. Atlantis does not interfere with Terraform remote state in any way. Under the hood, Atlantis is simply executing terraform plan and terraform apply.

Q: How does Atlantis locking interact with Terraform locking?

A: Atlantis provides locking of pull requests that prevents concurrent modification of the same infrastructure (Terraform project) whereas Terraform locking only prevents two concurrent terraform apply's from happening.

Terraform locking can be used alongside Atlantis locking since Atlantis is simply executing terraform commands.

Q: How to run Atlantis in high availability mode? Does it need to be?

A: Atlantis server can easily be run under the supervision of an init system like upstart or systemd to make sure atlantis server is always running.

Atlantis, by default, stores all locking and Terraform plans locally on disk under the --data-dir directory (defaults to ~/.atlantis). If multiple Atlantis hosts are run by utilizing a shared redis backend, then it's important that the data-dir is using a shared filesystem between hosts.

However, if you were to lose the data, all you would need to do is run atlantis plan again on the pull requests that are open. If someone tries to run atlantis apply after the data has been lost then they will get an error back, so they will have to re-plan anyway.

Q: How to add SSL to Atlantis server?

A: First, you'll need to get a public/private key pair to serve over SSL. These need to be in a directory accessible by Atlantis. Then start atlantis server with the --ssl-cert-file and --ssl-key-file flags. See atlantis server --help for more information.

Q: Can Atlantis detect infrastructure drift?

A: Yes. When the --enable-drift-detection flag is set, Atlantis exposes API endpoints for drift detection, status, and remediation. Drift detection works by running terraform plan against the specified branch/ref (outside of a pull request context) and analyzing the plan output for changes. You can trigger drift detection via POST /api/drift/detect and retrieve cached results via GET /api/drift/status. See API Endpoints for details.

Q: How do I set up scheduled drift detection?

A: Atlantis provides the drift detection API but does not include a built-in scheduler. You can use an external scheduler (e.g., cron, CI/CD pipelines, or a monitoring tool) to periodically call POST /api/drift/detect. Configure drift webhooks to receive Slack or HTTP notifications when drift is detected.

Q: How can I get Atlantis up and running on AWS?

A: There is terraform-aws-atlantis project where complete Terraform configurations for running Atlantis on AWS Fargate are hosted. Tested and maintained.