6.2.2 Ensure That the 'Log_connections' Database Flag for Cloud SQL PostgreSQL Instance Is Set to 'On'

Information

Enabling the log_connections setting causes each attempted connection to the server to be logged, along with successful completion of client authentication. This parameter cannot be changed after the session starts.

Rationale:

PostgreSQL does not log attempted connections by default. Enabling the log_connections setting will create log entries for each attempted connection as well as successful completion of client authentication which can be useful in troubleshooting issues and to determine any unusual connection attempts to the server. This recommendation is applicable to PostgreSQL database instances.

Impact:

Turning on logging will increase the required storage over time. Mismanaged logs may cause your storage costs to increase. Setting custom flags via command line on certain instances will cause all omitted flags to be reset to defaults. This may cause you to lose custom flags and could result in unforeseen complications or instance restarts. Because of this, it is recommended you apply these flags changes during a period of low usage.

Solution

From Google Cloud Console

Go to the Cloud SQL Instances page in the Google Cloud Console by visiting https://console.cloud.google.com/sql/instances.

Select the PostgreSQL instance for which you want to enable the database flag.

Click Edit.

Scroll down to the Flags section.

To set a flag that has not been set on the instance before, click Add item, choose the flag log_connections from the drop-down menu and set the value as on.

Click Save.

Confirm the changes under Flags on the Overview page.

From Google Cloud CLI

Configure the log_connections database flag for every Cloud SQL PosgreSQL database instance using the below command.

gcloud sql instances patch <INSTANCE_NAME> --database-flags log_connections=on

Note:
This command will overwrite all previously set database flags. To keep those and add new ones, include the values for all flags to be set on the instance; any flag not specifically included is set to its default value. For flags that do not take a value, specify the flag name followed by an equals sign ("=").

Default Value:

By default log_connections is off.

See Also

https://workbench.cisecurity.org/benchmarks/9562