The standard and most efficient method for applying unique configurations to multiple devices using Junos PyEZ involves a combination of a templating engine and a structured data file. A Jinja2 template defines the base configuration structure with placeholders for variables. A YAML file is then used to store the unique, per-device data, such as hostnames and IP addresses. A Python script leverages Junos PyEZ to read the YAML data, render the Jinja2 template with that data to create a device-specific configuration, and then apply it to the target machine.

A. an SCP module: The SCP module is a utility for securely transferring files to or from a device. It does not generate or apply the configuration itself.

B. a BSON data file: BSON is a binary-encoded format for JSON-like data. While it can store data, YAML is the human-readable, industry-standard format commonly used and documented for this automation workflow.

1. Juniper Networks TechLibrary, Junos PyEZ Developer Guide, "Using Configuration Templates to Configure Junos Devices": This official guide explicitly details the process. It states, "You can use Jinja2 templates in conjunction with Junos PyEZ to generate a configuration and load it onto a device... You can define the variables in a YAML or JSON file and load the file in the application." This section provides a complete example using a Jinja2 template and a YAML variables file to configure an interface.

2. Day One: Automating Junos with PyEZ, Second Edition, Chapter 4: "Provisioning a New Device": This book demonstrates a practical use case. Page 58 shows creating a YAML file (new-devices.yml) to store device-specific variables (hostname, IP address). Page 59 presents a Jinja2 template (config-template.j2) that uses these variables. The accompanying Python script combines them to generate and load the unique configuration for each device.