Dbname for Standby Database in Mgmt_target_properties Shows Primary db Unique Name (Doc ID 1067738.1)

Last updated on AUGUST 31, 2021

Applies to:

Symptoms

The DBName from the repository table MGMT$TARGET_PROPERTIES does not match with the DBName which is generated by dynamic property DBName (defined in $ORACLE_HOME/sysman/admin/metadata/oracle_database.xml) which originally derives from db_unique_name from v$parameter. This causes multiple dataguard problems similar to those described in note:416263.1

Issuing the following statement at sqlplus on the standby database:-

select property_value from mgmt_target_properties
where property_name = 'DBName'
and target_guid = (select target_guid from mgmt_targets where target_name ='<target_name of standby>');

returns the database unique name of the primary .

whereas:-

(select * from (SELECT name, value database_name
FROM v$parameter
WHERE (name = 'db_unique_name'
OR name = 'db_name')
AND value IS NOT NULL
ORDER BY name DESC)
where rownum = 1 )

returns the correct and expected database unique name of the standby, when issued on the standby.

Although this causes the same type of symptoms as note:416263.1 the underlying cause is different.
This is not bug:5554439 because the oracle_database.xml file is the one supplied by the fix to this bug.

Other symptoms are:-

the database home page for the standby shows it to be a primary database
But elsewhere, for example. in dgmgrl and on the dataguard home page, the standby is shown correctly as a standby.

Cause

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