Validating template configurations before and after application on devices

Summary

The key components involved in the template configuration validation process are:

  • System validator: Performs automated checks to ensure device compatibility and configuration integrity

  • Target device: The network device receiving the template configuration

  • Template configuration: The configuration settings being applied to the device

  • Rollback mechanism: System capability to restore original device state if validation fails

Workflow

These stages describe how template configuration validation works:

  1. The system performs pre-application validation checks before deploying the template on the target device.
    • Ensure that the target device model and version are supported.
    • Cluster and container checks -The device must not be part of a cluster or multi-instance.
    • Model mapping validation - Model mapping for the target device model exists and is valid.
    • Sanity check of template parameter values. For example, two variables used as IP addresses of interfaces must not have the same value.
  2. The system applies the template configuration to the target device after successful pre-application validation.
  3. The system performs post-application validation checks to ensure the applied configurations are valid.
    • Interface configuration validation. For example, variables used for the IP address fields of two or more interfaces must not have the same IP address values.
    • Routing policy validation. For example, the IPv4 address in BGP neighbor configurations must not overlap with the IP address of any interface.
    If the validation checks that are done at the end of the task to apply the template on the device fail, any applied configurations are rolled back and the device is restored to it's original state.