MAA - Oracle 10gR2 Redo Transport and Network Best Practices

Maximum Availability Architecture
Oracle Active Data Guard
Oracle Data Guard 11g
Introduction ....................................................................................................... 2
Typical Use Cases .............................................................................................. 3
Read-Only Applications and Application Workloads ............................. 3
Operations Allowable On a Read-Only Database .............................. 3
Operations Disallowed On a Read-Only Database ............................ 4
Typical Read-Only Configurations ............................................................. 4
Reader Farms: Scaling Read-Only Workload ........................................... 5
Accommodating Read-Mostly Applications ............................................. 6
Setup and Installation ....................................................................................... 6
Best Practices for Active Data Guard ............................................................ 7
How to Check if Active Data Guard is Already Enabled ....................... 7
General Best Practices .................................................................................. 7
Enabling Active Data Guard ....................................................................... 8
Evaluating if Applications are Suitable for Read-Only Database ........ 10
Application Connection Management ..................................................... 10
Managing Initial Client Connections ................................................... 10
Managing Existing Connections for Unplanned Outages................ 11
Recovering from RAC Apply Instance Node Failure ....................... 12
Monitoring Performance ........................................................................... 13
Redo Transport....................................................................................... 13
Apply Services ......................................................................................... 14
Query SCN .................................................................................................. 15
Avoiding ORA-01555 errors ................................................................ 16
Performance and Scalability ........................................................................... 17
Redo Apply Performance .......................................................................... 17
Role Transition Performance .................................................................... 18
Application Scalability ................................................................................ 18
Conclusion ........................................................................................................ 20
Appendix A: Enabling Active Data Guard on A Standby Database That
Requires Additional Recovery ....................................................................... 21
Appendix B: Using Database Links for Read Mostly Applications ......... 23
Appendix C: Tuning Redo Apply ................................................................. 28
Appendix D: Tuning Queries on the Standby Database ........................... 34
Oracle Active Data Guard: Oracle Data Guard 11g Page 1