By Franck Pachot

.
In the part I we have seen the properties that are imported when you add a database to the configuration, and which are then managed by the broker. Now we will list the properties that are managed by the broker, but whose default value is not imported from the instance parameters.

LogXpt properties

Here are the properties from primary database where I removed those we have seen in previous Part I:


DGMGRL> show database verbose demo11;
...
  Properties:
...
    DGConnectIdentifier             = '//vm112/DEMO12'
    LogXptMode                      = 'ASYNC'
    RedoRoutes                      = ''
    DelayMins                       = '0'
    Binding                         = 'optional'
    MaxFailure                      = '0'
    ReopenSecs                      = '300'
    NetTimeout                      = '30'
    RedoCompression                 = 'DISABLE'
    LogShipping                     = 'ON'
    InconsistentLogXptProps         = '(monitor)'
    StandbyArchiveLocation          = 'USE_DB_RECOVERY_FILE_DEST'
    AlternateLocation               = ''
...

They are related with log shipping destination. When I enabled the configuration, the LOG_ARCHIVE_DEST have been set with those values:


SQL> show parameter log_archive_dest_1
 
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
log_archive_dest_1                   string      location=USE_DB_RECOVERY_FILE_
                                                 DEST, valid_for=(ALL_LOGFILES,
                                                  ALL_ROLES)
log_archive_dest_2                   string      service="//vm112/DEMO12", ASYN
                                                 C NOAFFIRM delay=0 optional co
                                                 mpression=disable max_failure=
                                                 0 max_connections=1 reopen=300
                                                  db_unique_name="demo12" net_t
                                                 imeout=30, valid_for=(online_l
                                                 ogfile,all_roles)
log_archive_dest_state_1             string      enable
log_archive_dest_state_2             string      enable

Now, I manage them from the Data Guard broker:


DGMGRL> edit database demo12 set property LogXptMode='SYNC';
Property "logxptmode" updated

which has run the following ALTER SYSTEM:


ALTER SYSTEM SET log_archive_dest_2='service="//vm112/DEMO12"','SYNC AFFIRM delay=0 optional compression=disable max_failure=0 max_connections=1 reopen=300 db_unique_name="demo12" net_timeout=30','valid_for=(online_logfile,all_roles)' SCOPE=BOTH;

When we go to SYNC, the destination is set to SYNC (wait for log shipping) and AFFIRM (wait for log write)

Properties – LOG_ARCHIVE_DEST attributes

Here is the correspondence. The properties change the LOG_ARCHIVE_DEST attributes to set log shipping.

Broker property LOG_ARCHIVE_DEST
RedoRoutes LOG_ARCHIVE_DEST_n
DGConnectIdentifier service=
LogXptMode SYNC/ASYNC,AFFIRM/NOAFFIRM
DelayMins delay=
Binding MANDATORY/OPTIONAL
MaxFailure max_failure=
ReopenSecs reopen=
NetTimeout net_timeout=
RedoCompression compression=
LogShipping LOG_ARCHIVE_DEST_STATE_n
StandbyArchiveLocation location=
AlternateLocation location=

Not imported

I’ll show that those parameters are not imported when we create a configuration. Here I remove and re-create the configuration and I still have the LOG_ARCHIVE_DEST as SYNC.


DGMGRL> REMOVE CONFIGURATION;
Removed configuration
DGMGRL> CREATE CONFIGURATION demo11 AS PRIMARY DATABASE IS demo11 CONNECT IDENTIFIER IS '//vm111/DEMO11';
Configuration "demo11" created with primary database "demo11"
DGMGRL> ADD DATABASE demo12 AS CONNECT IDENTIFIER IS '//vm112/DEMO12';
Database "demo12" added
DGMGRL> ENABLE CONFIGURATION demo11;
Enabled.

But:


SQL> show parameter log_archive_dest_2

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
log_archive_dest_2                   string      service="//vm112/DEMO12", ASYN
                                                 C NOAFFIRM delay=0 optional co
                                                 mpression=disable max_failure=
                                                 0 max_connections=1 reopen=300
                                                  db_unique_name="demo12" net_t
                                                 imeout=30, valid_for=(online_l
                                                 ogfile,all_roles)

The log shipping attributes have been set to the broker properties defaults. This is the main difference from the properties we have seen in Part I.
Never change the LOG_ARCHIVE_DEST with ALTER SYSTEM. they are managed by the broker. And don’t forget to set those properties if you re-create the broker configuration.