How do I identify which Amazon RDS DB parameters are in custom parameter groups and which are in default parameter groups?

Short description

You can modify parameters for custom DB parameter groups to resolve incompatible-parameter issues. To do so, compare the differences between the custom parameter group settings to determine the values that are set by default. For example, you can review default values to identify the parameters that initiated the incompatible-parameters issue. Then, compare the custom parameter group to the default parameter group for your database engine.

Resolution

Note: If you receive errors when running AWS Command Line Interface (AWS CLI) commands, make sure that you're using the most recent AWS CLI version.

Using the Amazon RDS console

1. Open the Amazon RDS console, and select the Region that contains the Amazon RDS DB instance.
2. Choose Parameter Groups from the navigation pane.
3. Choose two parameter groups that you want to compare, and then choose Parameter group actions.
4. Choose Compare Parameters.

The result is a Parameter Comparison table that lists all parameters and values. Review the Parameter Comparison table to see the values of parameters for both default and custom parameter groups.

Using the AWS CLI

Use the describe-db-parameters and describe-db-cluster-parameters commands in the AWS CLI to compare parameter groups.

Run the following command to view the settings for a parameter group, including the source for each:

aws rds describe-db-parameters --db-parameter-group-name INSERT-YOUR-PG-NAME-HERE --region INSERT-REGION-HERE

To list the default value for the engine family, use the same command. Or, use the describe-engine-default-parameters command for database-level parameters and the describe-engine-default-cluster-parameters command for cluster-level parameters.

The following example shows the default parameters for the MySQL engine version 8.0 parameter group family:

aws rds describe-engine-default-parameters --db-parameter-group-family mysql8.0

Note: There isn't an AWS CLI command that compares two parameter groups at the same time. This feature is available only in the Amazon RDS console. But you can use the AWS CLI command --output text to list the results in plaintext rather than the default JSON format. After you do that, compare the plaintext files that list the parameter groups.

Related information

How do I resolve issues with an Amazon RDS database that is in an incompatible-network state?

How can I fix an Amazon RDS DB instance that is stuck in the incompatible-parameters status?

Working with parameter groups