Vault agent Auto-Auth token file method

The token_file method reads in an existing, valid Vault token from a file, and uses that token in lieu of authenticating itself. While it's a first class auto-auth method for all intents and purposes, it naturally doesn't authenticate itself, as it requires a token from elsewhere. Like other auto-auth methods, Agent will attempt to renew the token, as appropriate.

This auto-auth method is especially useful when testing Vault Agent without needing to set up any authentication methods in Vault. For long-running Agent processes, we strongly recommend another auto-auth method, such that Agent is issuing its own authentication requests to Vault.

Configuration

• token_file_path (string: required) - The path to the file with the token inside. This token cannot be a wrapping token.

Example configuration

An example configuration, using the token_file method to enable auto-auth, follows:

pid_file = "./pidfile"

vault {
  address = "https://127.0.0.1:8200"
}

auto_auth {
  method {
    type = "token_file"

    config = {
      token_file_path = "/home/username/.vault-token"
    }
  }
}


api_proxy {
  use_auto_auth_token = true
}

listener "tcp" {
  address = "127.0.0.1:8100"
  tls_disable = true
}

template {
  source      = "/etc/vault/server.key.ctmpl"
  destination = "/etc/vault/server.key"
}

template {
  source      = "/etc/vault/server.crt.ctmpl"
  destination = "/etc/vault/server.crt"
}