Compute – SSH Keys

SSH keys are used to securely access Verda compute instances. With Terraform, you can manage SSH keys declaratively and attach them to instances as part of your infrastructure-as-code workflow.

Managing SSH keys in Terraform ensures access is reproducible, auditable, and version controlled.

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What this page covers

• Creating and managing SSH keys with Terraform

• Attaching SSH keys to compute instances

• Using existing SSH keys

• Rotating and removing keys safely

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Basic example

resource "verda_ssh_key" "main" {
  name        = "admin-key"
  public_key = file("~/.ssh/id_rsa.pub")
}

Once created, the SSH key can be attached to one or more compute instances.

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Required fields

The following arguments are required when creating an SSH key:

• name (String) A human-readable name for the SSH key.

• public_key (String) The SSH public key material (for example, the contents of id_rsa.pub).

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Attaching SSH keys to instances

To allow SSH access to an instance, reference one or more SSH key IDs in the instance configuration:

resource "verda_instance" "example" {
  description   = "GPU instance for training"
  hostname      = "training-01"
  image         = "ubuntu-22.04"
  instance_type = "1B200.30V"

  ssh_key_ids = [
    verda_ssh_key.main.id
  ]
}

You can attach multiple SSH keys if multiple users or automation systems require access.

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Using existing SSH keys

If an SSH key already exists in Verda, you can reference it by ID without recreating it:

resource "verda_instance" "example" {
  # ...

  ssh_key_ids = [
    "existing-ssh-key-id"
  ]
}

This is useful when gradually adopting Terraform for existing infrastructure.

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SSH key generation

If you do not already have an SSH key pair, you can generate one locally:

ssh-keygen -t ed25519 -C "[email protected]"

Then reference the generated public key file in Terraform:

public_key = file("~/.ssh/id_ed25519.pub")

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Key rotation and removal

To rotate an SSH key:

1. Create a new verda_ssh_key resource

2. Attach it to your instances

3. Apply the Terraform changes

4. Remove the old key from configuration

5. Apply again

This avoids accidental lockout during key rotation.

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Importing existing SSH keys

You can import an existing SSH key into Terraform state:

terraform import verda_ssh_key.main <ssh-key-id>

After importing, run:

terraform plan

Update your configuration until Terraform reports no changes.

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Best practices

• Use one SSH key per user or automation system

• Avoid sharing private keys between users

• Rotate keys periodically

• Manage SSH keys through Terraform for consistent access control

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Troubleshooting

• SSH access denied Ensure the correct SSH key is attached to the instance and that you are using the matching private key.

• Key not applied to instance Confirm the instance was updated after adding the SSH key and that ssh_key_ids is set correctly.

• Lost access after changes Always add new keys before removing old ones when rotating credentials.