Compute – Startup Scripts

Startup scripts allow you to run initialization logic automatically when a Verda compute instance is created. They are commonly used to install system packages, configure services, prepare machine learning environments, or perform other one-time setup tasks.

In Terraform, startup scripts are managed as first-class resources using verda_startup_script and then attached to compute instances. This separation makes startup scripts reusable across multiple instances and environments.

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How startup scripts work

• Startup scripts run once, during the first boot of an instance.

• Scripts are executed as root.

• Updating a startup script does not affect existing instances unless they are recreated.

• A single startup script can be reused by multiple instances.

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Defining a startup script

Create a startup script using the verda_startup_script resource. The script must include a valid shebang (for example, #!/bin/bash).

resource "verda_startup_script" "basic" {
  name = "basic-setup"
  script = <<-EOF
    #!/bin/bash
    set -e

    apt-get update
    apt-get install -y curl wget git
  EOF
}

For more complex setups, startup scripts can install Docker, ML frameworks, or perform custom configuration steps.

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Attaching a startup script to an instance

Once defined, reference the startup script from a compute instance using startup_script_id:

resource "verda_instance" "example" {
  name              = "training-01"
  instance_type     = "gpu-a100-80gb"
  image             = "ubuntu-24.04-cuda-12.8-open-docker"
  startup_script_id = verda_startup_script.basic.id

  ssh_key_ids = [verda_ssh_key.main.id]
}

The script will be executed automatically when the instance is created.

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Common use cases

Startup scripts are typically used for:

• Installing system packages and drivers

• Setting up Python, CUDA, or ML frameworks

• Configuring users, permissions, or SSH settings

• Pulling application code or model artifacts

• Starting background services or agents

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Best practices

• Use set -e to fail fast on errors.

• Keep scripts idempotent where possible.

• Store scripts in Terraform using heredocs or external files (file()).

• Avoid hardcoding secrets — use environment variables or secure storage.

• Treat startup scripts as immutable: recreate instances when scripts change.

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Importing existing startup scripts

Existing startup scripts can be imported into Terraform state:

terraform import verda_startup_script.example <startup-script-id>

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Notes and limitations

• Startup scripts run only on initial creation.

• Changes to startup_script_id typically require instance replacement.

• Logs and side effects depend on your script implementation.

For the full schema and advanced examples, see the Verda Startup Script resource documentation.