Show the Data Guard broker configuration and database status (DGMGRL)

Command

# From the shell (connect with a password; also required for switchover/failover):
dgmgrl sys@<primary_db_unique_name>
SHOW CONFIGURATION VERBOSE;
SHOW DATABASE VERBOSE '<standby_db_unique_name>';
# Monitorable properties:
SHOW DATABASE '<primary_db_unique_name>' 'LogXptStatus';
SHOW DATABASE '<standby_db_unique_name>' 'RecvQEntries';
SHOW DATABASE '<primary_db_unique_name>' 'InconsistentLogXptProps';
SHOW DATABASE '<standby_db_unique_name>' 'StatusReport';

What it does

Shows the overall broker configuration status (SUCCESS/WARNING/ERROR), the protection mode, each database's role, transport/apply lag and inconsistencies between the broker and the spfile.

When to use it

Before and after every Data Guard operation (switchover, failover, parameter change); in the daily health check.

Caution

Read-only. While the broker is enabled, do not change Data Guard parameters such as log_archive_dest_n or log_archive_config with SQL; the broker overwrites them with its own values. Make changes with EDIT DATABASE ... SET PROPERTY, and in 19c+ use EDIT DATABASE ... SET PARAMETER for initialization parameters.