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2 Safe Harbor Statement The following is intended to outline our general product direction. It is intended for information purposes only, and may not be incorporated into any contract. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. The development, release, timing, and pricing of any features or functionality described for Oracle s products may change and remains at the sole discretion of Oracle Corporation. 2

3 Oracle (Active) Data Guard Best Practices and New Features Deep Dive Mahesh Girkar, Senior Director, Database HA Development Nitin Karkhanis, Director, Data Guard Broker Development October 22, 2018

4 Data Guard: Real-time Data Protection and Availability Included with Oracle Database Enterprise Edition Primary Data Center DR Data Center Automatic Block Repair Data Guard Broker (Enterprise Manager Cloud Control or DGMGRL) 4

5 Active Data Guard: Advanced Capabilities A licensable option to the Oracle Database Enterprise Edition Primary Data Center DR Data Center Offload read-only workload to open standby database Zero data loss at any distance Automatic Block Repair Data Guard Broker (Enterprise Manager Cloud Control or DGMGRL) Offload Fast Incremental Backups 5

6 Agenda 1 2 What s new with Oracle (Active) Data Guard in 18c? A peek at the future of Oracle (Active) Data Guard. 6

7 Agenda 1 2 What s new with Oracle (Active) Data Guard in 18c? A peek at the future of Oracle (Active) Data Guard. 7

8 (Active) Data Guard New Features Multi-Instance Redo Apply Enhancement Extend Active Data Guard (ADG) environments for Data Warehousing Faster application response after a role transition Protect Primary database from lost write storage failures Extend the footprint of Active Data Guard applications Better protection against failed logins 8

9 Multi-Instance Redo Apply Enhancements Introduced in Oracle Database 12c Release 2 Multi-Instance Redo apply now works with Block Change Tracking enabled Block Change Tracking on a standby requires an Active Data Guard license 9

10 Data Guard and Database Nologging Improvements* *Available on Engineered Systems and Oracle Cloud only Two new modes are added as alternatives to the FORCE LOGGING mode: 1. Standby Nologging for Load Performance Ensures that standbys will receive the nonlogged data changes with minimum impact to the speed of loading at the primary. The standby can transiently have nonlogged blocks. These nonlogged blocks will be automatically resolved by managed standby recovery. 2. Standby Nologging for Data availability Ensures that all standbys have the data when the primary load commits, but at the cost of throttling the speed of loading data at the primary. The standbys will never have any nonlogged blocks. These new modes cause Multi-Instance Redo Apply to return an error Single Instance Redo apply must be manually enabled to proceed past the nologging operation. 10

11 Preserve Buffer Cache During Role Change* Read/Write Primary Failed Primary Read Active Data Guard Standby Read/Write Primary The database buffer cache state will be maintained on an ADG standby during a role change Automatic, nothing to set up Services need to be configured correctly so that users who stay connected are on a service that is valid in both PHYSICAL_STANDBY and PRIMARY roles. *First Release Caveat: Only available on non-rac Active Data Guard standby databases. 11

12 Lost write protection on Primary Lost writes cause serious corruptions due to stale blocks appearing as good Applications running on the primary can get incorrect stale data. Prior features focused on detection of lost writes on the standby during redo apply. This causes data loss dilemmas, if time elapses between occurrence of lost write and its detection. Lost write detection on primary prevents inconsistencies from spreading Database records SCN of data block being written in a shadow block Requires the configuration of a new tablespace type called shadow tablespace that contains shadow blocks The SCN of data blocks that are read into the buffer cache are validated with its SCN saved in the shadow blocks Design is efficient and has minimal overhead Standbys remain intact! Applications do not get inconsistent results! No need to failover! 12

13 Creating Private Temporary Tables on Active Data Guard Creating Private (Local) Temporary Tables is supported on an Active Data Guard standby database They are stored in memory on the standby Visible only to the session that created it Dropped at the end of a transaction or session 13

14 Control Login-Attempts on Active Data Guard The ADG_ACCOUNT_INFO_TRACKING parameter extends the control of user account security information and reaction LOCAL (default value) continues to enforce the existing behavior Maintains local copy of users account information in the standby's in-memory view Login failures are only tracked locally on a per database basis Logins are denied when the failure maximum is reached GLOBAL triggers the new, secure behavior Maintains a single global copy of users account information across all Data Guard databases Login failures across all databases in the Data Guard configuration count towards the maximum count Logins anywhere will be denied when the count is reached 14

15 New Data Guard Broker Commands Enhanced Scripting and Execution commands New VALIDATE commands 15

16 SHOW ALL DGMGRL> show all; debug echo time OFF OFF OFF observerconfigfile = observer.ora 16

17 SET DEBUG ON OFF DGMGRL> set debug on; DGMGRL> connect Password:******** [W T10:07: :00] Connecting to database using boston. [W T10:07: :00] Attempt logon as SYSDBA [W T10:07: :00] Successfully logged on as SYSDBA... Connected as SYSDBA. 17

18 SET ECHO ON OFF DGMGRL> set echo off; DGMGRL> edit database boston set property logxptmode=async; Property "logxptmode" updated DGMGRL> set echo on; DGMGRL> edit database boston set property logxptmode=sync; edit database dgc2 set property logxptmode=sync; Property "logxptmode" updated 18

19 SET TIME ON OFF DGMGRL> set time on; DGMGRL 10:21:04> failover to boston; Performing failover NOW, please wait Failover succeeded, new primary is Boston DGMGRL 10:21:25> 19

20 DGMGRL Scripting Script File: commands.cli set echo on connect edit database boston set property logxptmode=sync; 20

21 DGMGRL Scripting connect Connected to boston" Connected as SYSDG. edit database boston set property logxptmode=sync; Property "logxptmode" updated 21

22 VALIDATE DATABASE SPFILE Validates parameter settings between the primary and a standby database DGMGRL> validate database boston spfile ; Connecting to boston. Connecting to newyork. No parameter differences found. Good result à no differences 22

23 VALIDATE DATABASE SPFILE (Cont d) DGMGRL> validate database newyork spfile ; Connecting to boston". Connecting to newyork". Parameter settings with different values: aq_tm_processes: boston (PRIMARY) : 8 newyork : 9 use_large_pages: boston (PRIMARY) : TRUE newyork : NOT SPECIFIED 23

24 VALIDATE NETWORK CONFIGURATION Validates the network setup between all databases in the configuration DGMGRL> validate network configuration for boston; Connecting to instance bos" on database boston"... Connected to boston" Checking connectivity from instance bos" on database boston to instance den" on database denver"... Succeeded. Connecting to instance den" on database denver"... Connected to denver" Checking connectivity from instance den" on database denver to instance bos" on database boston"... Succeeded. Oracle Clusterware on database boston" is available for database restart. 24

25 VALIDATE STATIC CONNECT IDENTIFIER Validates the static connect identifier setup in unmanaged environments Applies to databases in the Data Guard configuration that do not use Oracle RAC RAC One Node Oracle Restart Requires a static entry so that the Broker can Restart a database during switchover Convert from Snapshot Standby back to Physical Standby Reinstate a failed primary as a standby Also run as part of VALIDATE NETWORK CONFIGURATION, if necessary 25

26 Agenda 1 2 What s new with Oracle (Active) Data Guard in 18c? A peek at the future of Oracle (Active) Data Guard. 26

27 (Active) Data Guard Features for the Future Improved Data Guard Multi-Instance Redo Apply Active Data Guard DML Redirection New Parameters for tuning automatic outage resolution with Data Guard Buffer Cache on Active Data Guard preserved after role transition for RAC Flashback Database enhancements with Data Guard 27

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