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Hi, Checking if the Far Sync instance is configured to restart automatically after reboot / shutdown of the host / cluster: $ crsctl stat res ora.fdb1.db -f |grep AUTO_START AUTO_START= restore "restore" means that after restart, the database will remain at the previous state it was before. Changing the cluster to startup the database in any case. $ crsctl stat res ora.fdb1.db -f |grep AUTO_START AUTO_START= always Changing database to start always after reboot $ crsctl modify resource ora.fdb1.db -attr  AUTO_START= always -unsupported Modify the startup state: $ srvctl modify database -o mount View modified configuration $ srvctl config database -d fdb1 -all Database unique name: fdb1 Database name: fdb1 Oracle home: /oracle/product/12.1.0.2/dbhome_1 Oracle user: oracle Spfile: Password file: Domain: Start options: mount Stop options: immediate Database role: FAR_SYNC Management policy: AUTOMATIC Disk Groups: DATA Services: Database is enab...

I have just came across a meta parameter called DB_ULTRA_SAFE that sets the values for all of mentioned parameters in Far Sync Best Practice Recommendations (for Oracle 12.1) . When DB_ULTRA_SAFE=DATA_ONLY   • DB_BLOCK_CHECKING => MEDIUM.   • DB_LOST_WRITE_PROTECT => TYPICAL.   • DB_BLOCK_CHECKSUM => FULL. When DB_ULTRA_SAFE=DATA_AND_INDEX   • DB_BLOCK_CHECKING => FULL.   • DB_LOST_WRITE_PROTECT => TYPICAL.   • DB_BLOCK_CHECKSUM => FULL. When DB_ULTRA_SAFE=OFF   • When any of DB_BLOCK_CHECKING, DB_BLOCK_CHECKSUM, or DB_LOST_WRITE_PROTECT are explicitly set, no changes are made.

These are the steps of creating Far Sync instance in the command line: Create 12.1 primary db Create 12.1 physical standby Create regular standby DG broker configuration modify network file (on primary and standby) and add entries for the far_sync instance, add to tnsnames.ora on Primary hosts and standby hosts: FarSyncInst =   (DESCRIPTION =     (ADDRESS_LIST =       (ADDRESS = (PROTOCOL = TCP)(HOST = FarSyncHost)(PORT = 1521))     )     (CONNECT_DATA =       (SERVER = DEDICATED)       (SERVICE_NAME = FarSyncInst)       (UR=A)     )   )     Note: (UR=A) is needed to connect to a BLOCKED unmounted database instance. Copy tnsnames.ora to new farsync server – ensure all hosts mentioned in tnsnames are written also in /etc/hosts Add to listener.ora in far sync server LISTENER =   (DESCRIPTION_LIST =     (DESCRIPTION =     ...

Hi, This post is a continuation of my post, Using Standby as an Alternate for Far Sync (12c): Limitations and Considerations . It is for database administrators who want to set up Far Sync for the first time. Creating a Far Sync instance requires a number of manual steps and there are many parameters to consider or set. I recently ran numerous scenarios using Oracle™ Active Data Guard with a Far Sync instance. Our goals were to: • Check Far Sync functionality and reliability • Validate that Far Sync has a low footprint under heavy load After running a large number of benchmark scenarios, where we changed one parameter at a time, here are my recommendations for using Active Data Guard with Far Sync: The primary database, the standby database, and the Far Sync instance should all be using the same software version and patch level; if not, upgrade the database(s) to the latest version with the latest patch sets. Consider changing the following database initialization parameters...

Based on Oracle 12.1 The Recommended Data Guard configuration is in Maximum Availability mode, when using Far Sync which is located near the Primary: Primary Database  à Far Sync Instance - Network input/output (I/O) is synchronous (Sync). Far Sync Instance  à  Standby Database – Network I/O is asynchronous (Async). Primary Database  à  Standby Database  – As an alternate (when Far Sync is not reachable), network I/O is asynchronous (Async). Using SQL If you do not use Data Guard Broker (dgmgrl), use the parameters specified below. ·         Primary On the Primary Database Mandatory Parameters Parameter Value Remarks LOG_ARCHIVE_DEST_2 point to Far Sync service Alternate log_archive_dest_3 Switches to the standby destination, after the number of failures specified in the next parameter is reached. max_failure 1 This val...