MediaTailor configuration aliases troubleshooting guide

AWS Elemental MediaTailor provides systematic troubleshooting guidance for common configuration aliases issues and error scenarios.

Configuration alias validation errors

When configuration aliases are missing or invalid, MediaTailor returns specific error responses to help identify the issue.

Common error scenarios

The following table describes common configuration alias errors and their resolution steps:

Error	Cause	Resolution
HTTP 400: Invalid player parameter alias	Player parameter value not found in ConfigurationAliases	Verify that the player parameter value exists as a key in the corresponding ConfigurationAliases mapping
HTTP 400: Missing required configuration alias	Domain variable used without corresponding ConfigurationAliases entry	Add the missing player parameter to ConfigurationAliases with all required alias mappings
HTTP 400: Configuration validation failed	ConfigurationAliases structure is malformed or incomplete	Validate JSON structure and ensure all domain variables have corresponding aliases
Empty string replacement in URLs	Non-domain variable alias not found	Add missing alias mapping or provide default value in ConfigurationAliases

Validation checklist

Use the following checklist to validate your configuration aliases setup:

1. Domain variable coverage: Ensure all variables used in domain portions of URLs have corresponding ConfigurationAliases entries

2. Alias completeness: Verify that all possible player parameter values are included as keys in the alias mappings

3. JSON structure: Validate that the ConfigurationAliases JSON is properly formatted and nested

4. Parameter naming: Confirm that all player parameters use the player_params. prefix

5. Value consistency: Ensure alias values are valid for their intended use (URLs, profile names, etc.)

Debugging configuration alias resolution

Follow this systematic approach to debug configuration alias resolution issues.

Step-by-step debugging methodology

Use the following steps to identify and resolve configuration alias issues:

Configuration alias debugging procedure

1. Verify configuration structure: Confirm that your playback configuration includes properly formatted ConfigurationAliases

   {
       "ConfigurationAliases": {
           "player_params.example_param": {
               "alias1": "value1",
               "alias2": "value2"
           }
       }
   }

2. Check player parameter format: Ensure session initialization includes correctly formatted player parameters

   {
       "playerParams": {
           "example_param": "alias1"
       }
   }

3. Validate alias mapping: Confirm that the player parameter value ("alias1") exists as a key in the ConfigurationAliases mapping

4. Test with simple configuration: Start with a minimal configuration to isolate the issue

5. Monitor error responses: Check MediaTailor error responses for specific validation messages

6. Verify resolved URLs: Confirm that the final resolved URLs are valid and accessible

Configuration aliases best practices

Follow these best practices to ensure reliable configuration alias implementation.

Security considerations

Implement the following security measures when you use configuration aliases:

• Input validation: Validate all player parameter values before using them in alias resolution

• Alias value sanitization: Ensure alias values contain only expected characters and formats

• Domain restrictions: Limit domain aliases to trusted, controlled domains

• Access control: Restrict configuration modification to authorized personnel only

Performance optimization

Optimize configuration alias performance with these recommendations:

• Minimize alias count: Use only necessary aliases to reduce processing overhead

• Efficient naming: Use clear, consistent naming conventions for aliases and parameters

• Default values: Provide sensible default aliases for common use cases

• Configuration caching: Leverage MediaTailor's configuration caching for improved performance

Maintenance and monitoring

Maintain reliable configuration alias operations with these practices:

• Regular validation: Periodically validate that all alias mappings are current and functional

• Error monitoring: Monitor for HTTP 400 errors related to missing or invalid aliases

• Documentation: Maintain clear documentation of all alias mappings and their purposes

• Testing procedures: Implement comprehensive testing for all alias combinations