12c??? - Active Data Guard Far Sync
- by Jian Zhang(??)
??
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Active Data Guard Far Sync?Oracle 12c????(???Far Sync Standby),Far Sync?????????????(Primary Database)?????????Far Sync??,??(Primary Database) ??(synchronous)??redo?Far Sync??,??Far Sync????redo??(asynchronous)???????(Standby Database)???????????????????????Far Sync????????,init?????????,????????
??redo ????Maximum Availability??,???????????(Primary Database)?????????Far Sync??,??(Primary Database)??(synchronous)??redo?Far Sync??,???????(zero data loss),?????Far Sync????,??????,??????????????Far Sync????redo??(asynchronous)???????(Standby Database)?
??redo ????Maximum Performance??,???????????(Primary Database)?????????Far Sync??,??(Primary Database) ????redo?Far Sync??,??Far Sync???????redo?????????(Standby Database)????????????????(Standby Database)??redo???(offload)?
Far Sync????Data Guard ????(role transitions)????,?switchover/failover?????12c?????
???????Data Guard ????,?switchover/failover,???????????????Far Sync??,??Far Sync????????????????????
???Far Sync???????,??????????????2?Far Sync??,????????
???????Far Sync?????
Far Sync???
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????Far Sync
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1. ??Data Guard,???11.2??,??????«Active Database Duplication for A standby database»
2. ????Far Sync??,Far Sync????????,init?????????,????????
??Far Sync???????,?????:
SQL> ALTER DATABASE CREATE FAR SYNC INSTANCE CONTROLFILE AS '/tmp/controlfs01.ctl';
3. ????redo?????Far Sync??,????LOG_ARCHIVE_DEST_2??:
LOG_ARCHIVE_DEST_2='SERVICE=dg12cfs SYNC AFFIRM MAX_FAILURE=1 ALTERNATE=LOG_ARCHIVE_DEST_3
VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=dg12cfs'
4. ??Far Sync??????redo???,??Far Sync??LOG_ARCHIVE_DEST_2??:
LOG_ARCHIVE_DEST_2='SERVICE=dg12cs ASYNC
VALID_FOR=(STANDBY_LOGFILES,STANDBY_ROLE) DB_UNIQUE_NAME=dg12cs'
5. ????Far Sync???????,??????????????2?Far Sync???
6. ???????:
SQL> select * from V$DATAGUARD_CONFIG;
DB_UNIQUE_NAME PARENT_DBUN DEST_ROLE CURRENT_SCN CON_ID
------------------------------ ------------------------------ ----------------- ----------- ----------
dg12cfs dg12cp FAR SYNC INSTANCE 682995 0
dg12cs dg12cfs PHYSICAL STANDBY 682995 0
dg12cp NONE PRIMARY DATABASE 683138 0
????????????????:Oracle_12c_Active_Data_Guard_Far_Sync_v1.pdf
