PostgreSQL instances should have the 'log_error_verbosity' flag set to 'DEFAULT' or stricter

Description

The log_error_verbosity flag controls the verbosity/details of messages logged. Valid values are:

  • TERSE
  • DEFAULT
  • VERBOSE

TERSE excludes the logging of DETAIL, HINT, QUERY, and CONTEXT error information. VERBOSE output includes the SQLSTATE error code, source code file name, function name, and line number that generated the error.

Ensure an appropriate value is set to DEFAULT or stricter.

Rationale

Auditing helps in troubleshooting operational problems and also permits forensic analysis. If log_error_verbosity is not set to the correct value, too many details or too few details may be logged. This flag should be configured with a value of DEFAULT or stricter. 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 the 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 flag changes during a period of low usage.

  • WARNING: This patch modifies database flag values, which may require your instance to be restarted. Check the list of supported flags -https://cloud.google.com/sql/docs/postgres/flags - to see if your instance will be restarted when this patch is submitted.
  • Note: some database flag settings can affect instance availability orn stability and remove the instance from the Cloud SQL SLA. For information about these flags, see Operational Guidelines.
  • Note: Configuring the above flag does not require restarting the Cloud SQL instance.

Default value

By default, log_error_verbosity is DEFAULT.

Remediation

From the console

  1. Go to the Cloud SQL Instances page by visiting https://console.cloud.google.com/sql/instances
  2. Select the PostgreSQL instance for which you want to enable the database flag.
  3. Click Edit.
  4. Scroll down to the Flags section.
  5. To set a flag that has not been set on the instance before, click Add item, choose the flag log_error_verbosity from the drop-down menu and set appropriate value.
  6. Click Save
  7. Confirm your changes under Flags on the Overview page.

From the command line

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

    gcloud sql instances patch <INSTANCE_NAME> --database-flags
log_error_verbosity=<TERSE|DEFAULT|VERBOSE>

    Note: This command will overwrite all database flags previously set. To keep those and add new ones, include the values for all flags you want 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 (=).

References

  1. https://cloud.google.com/sql/docs/postgres/flags
  2. https://www.postgresql.org/docs/current/runtime-config-logging.html#RUNTIME-CONFIG-LOGGING-WHAT