Summary: Implement a validating admission webhook to ensure the correctness of fence agent parameters before fencing actual takes place (i.e validate FAR Template)

Description:

Currently, misconfigurations in fence agent parameters (e.g., incorrect IP addresses, invalid credentials, or improper fence_agent arguments) are easily made and can go unnoticed until a fencing operation is actually required. Discovering such issues during a critical event when fencing is desperately needed is too late and can lead to severe cluster instability or outages.

To mitigate this risk, we propose implementing a validating admission webhook for fencing parameters. This webhook would perform Rule-Based Validation:

Validate parameters against defined internal rules (e.g., ensuring required fields are present, checking for valid formats, confirming logical consistency between parameters).

Benefits:

• Early Detection of Misconfigurations: Catch parameter errors at deployment time, not during a critical failure.
• Increased Cluster Reliability: Ensures that fencing mechanisms are correctly configured and ready to function when required.
• Improved User Experience: Provides immediate, actionable feedback to users on incorrect configurations, preventing frustration during emergencies.

Notes:

• This ticket is a follow-up to discussions during recent reviews, acknowledging the importance of robust fencing parameter validation.