Oracle Data Guard OTN Case Study SWEDISH POST Corporate Profile Annual revenue EUR 2.5 billion 40,000 employees Serving 3 million homes and 800.000 businesses daily url: http://www.posten.se Disaster Recovery Solution Oracle Data Guard Redo Apply and SQL Apply Zero Data Loss Protection Offload reporting and backups from production databases OVERVIEW Swedish Post uses Oracle Data Guard for Disaster Recovery (DR) Protection for business critical data. It further maximizes the return on its DR investment by using Data Guard SQL Apply to offload reporting to standby databases for optimum performance of the production database server. INTRODUCTION Known as Posten in Sweden, the Swedish Post is one of the country s largest enterprises with over 40,000 employees and annual sales of EUR 2.5 billion. Swedish Post serves 3 million homes and 800,000 businesses each day. In addition to postal services, it provides competition-neutral financial services used by Sweden s leading banks. These services include bill payment, check cashing, payments to foreign payees, bank account transactions, and deposits of daily business receipts. BUSINESS STRATEGY The Swedish Post seeks to dramatically enhance customer service while simultaneously reducing its costs. It is accomplishing this by replacing its traditional postal locations with a service-rich Web portal providing ubiquitous access to its customers. To continue to deliver ground services required for parcel delivery, the Swedish Post has formed alliances with service oriented businesses such as retail chains, convenience stores, gas stations, and supermarkets. Since 2002 this initiative has doubled the number of postal service outlets available to Sweden s consumers, significantly enhancing customer convenience through closer proximity and substantially longer business hours. At peak, the Swedish Post was opening an average of 23 new points of sale every day. Business Critical Applications The new business model makes the operation of the Swedish Post more dependent than ever on the availability of its critical business applications. The Swedish Post uses Oracle Data Guard as a fundamental building block in their high availability architecture to implement local disaster recovery protection for an application critical to the success of the new logistics network. Named PABLO, it is responsible for tracking the delivery of every parcel posted at any one of over 2,000 locations across Sweden. The PABLO database includes a number of large tables with over 50 million rows each. PABLO is architected to handle a peak workload of 1,500,000 package registrations per day. 1
System Configuration 3 SUN Fire V880 Servers, 4x900MHz CPUs, 8GB memory SUN (HDS) 9980 SAN Solaris 64bit, version2.9 Oracle9i Database, Release 9.2.0.4 9 SUN Fire SF280 application servers, 750 MHz CPUs, 2 GB memory BEA Weblogic, version 6.1 The production database has a number of large tables with over 50 million rows each. At its peak the database will handle over 1,500,000 package registrations per day. Disaster Recovery Requirements The critical nature of the business application, both in terms of high availability and performance, results in the following requirements: Zero data loss in the case of failure of the production server. The total time to recover the production database to the point where it is again ready to process transactions following a complete failure must be less than 5 minutes after the decision has been made to fail over. Initially it is acceptable to have a local DR solution within a single facility, to protect against major subsystem failures that might result in the production database being unavailable for an extended period of time. Longer-term, the Swedish Post plans to include a remote facility in its DR architecture for additional protection against events that impact the production site. The DR solution must transparently accommodate this change without modification to the underlying DR infrastructure or requiring significant changes in operating procedures. The DR solution must accommodate planned hardware maintenance and regular testing of DR procedures, without requiring extra effort or downtime exceeding that specified in the above requirements. Minimizing financial costs is a significant requirement. The DR solution should not require additional staff to implement or manage. It must insure consistency of data in an automated fashion that does not increase management overhead for database administrators. The DR solution must not create additional processing overhead affecting the performance of the production system. Additionally, the DR solution should enable offloading the production system of the overhead of serving reporting users and backing up the production database. THE DISASTER RECOVERY SOLUTION: ORACLE DATA GUARD The Swedish Post chose Oracle Data Guard as its DR solution because it provides the best protection for Oracle data at the lowest cost. Data Guard protects data used by mission critical transaction processing systems. Data Guard also provides a built-in mechanism for data transport and maintenance of a separate reporting server, eliminating the need for custom code and other procedures to be developed in-house. Data Guard is able to address requirements for offloading processing from the production server without requiring any compromise in implementing the strongest possible DR protection for Oracle data. 2
Oracle Data Guard Configuration One standby database using Redo Apply (physical standby) Disaster Recovery Architecture The overall solution architecture is provided in Figure 1. The Swedish Post has implemented both Redo Apply (physical standby) and SQL Apply (logical standby) databases in the same Data Guard configuration. A second standby database using SQL Apply (logical standby) Maximum Availability Mode LGWR SYNC AFFIRM Fig. 1: Swedish Post Disaster Recovery Architecture Data Guard Redo Apply is used to create an exact replica of the production database for disaster recovery protection and to offload backups. It is configured in Maximum Availability protection mode. As quickly as new redo is generated on the production server, the LGWR SYNC redo transport mechanism sends it to the standby server. The standby server acknowledges its receipt and writes the redo to Standby Redo Logs (SRLs). Later, upon a log switch on the production database, the data in the SRLs on the standby server are archived and then applied to the standby database using the Managed Recovery Process (MRP) as part of media recovery. Meanwhile, the production database continues processing the next transaction as soon as it sees the acknowledgement that the previous transaction s redo has successfully reached the standby server. The second standby database is configured using Data Guard SQL Apply. SQL Apply uses the same redo transport mechanism as Redo Apply. The difference is that instead of using the MRP process to apply redo to the standby database, SQL Apply uses the Logical Standby Process (LSP), transforming the redo data back into SQL statements, and then applying them to the standby database. This creates a logical replica of the production database that is open for read access. This also enables additional schemas and indexes to be created to incorporate additional data and/or optimize the standby database for reporting purposes. 3
The Swedish Post utilizes a separate schema where data is extracted from the tables being maintained by SQL Apply, and aggregated with other data for Data Warehouse purposes. This results in the logical standby database having more tables and indices than the original production database. Oracle Recovery Manager (RMAN) is used to automate backups of both Redo Apply and SQL Apply databases. Data Guard and RMAN used together enable hot backups of the standby database. This allows Data Guard to continue to apply new redo that is being received from the primary database while a backup is in progress. Particularly appealing to the Swedish Post, RMAN also offers the added speed and convenience of being able to perform block recovery. Oracle Data Guard Benefits No lost business transactions and minimal interruption in service even in the face of a severe outage at the production site No DBA intervention required to maintain transactionally consistent standby databases Optimum transaction performance on primary database very little overhead for DR solution, offloading reporting and backup activity to standby servers No extra cost Data Guard is an integrated feature of the Oracle Database Server Enterprise Edition CONCLUSION: MISSION ACCOMPLISHED A stalwart public institution for 367 years, the Swedish Post is as much a symbol of security and tradition as Sweden s blue and yellow flag. At the same time, it has come to be associated with the accelerating pace of change in today s economy with the business mandate to be a modern and competitive messaging and logistics company. Along with this business challenge, comes the IT challenge to maintain high availability for its business applications even in the face of planned and unplanned outages. The ability of the Swedish Post to service its customers and alliance partners are impacted severely if critical application systems should fail. If a disaster strikes a production database, every minute of downtime translates into dissatisfied customers and alliance partners. Longer outages translate into real revenue lost to competitive delivery services, and greatly diminished confidence in the Swedish Post system. Swedish Post uses Oracle Data Guard to protect business critical application data. Oracle Data Guard provides the required level of data protection and disaster recovery, an essential element in any high availability architecture. It makes this contribution at the lowest possible cost. Data Guard provides additional reporting benefits through an extension of the infrastructure already in place for disaster recovery. Reporting and backups can be offloaded from transaction processing systems, enhancing application performance without compromising on data protection. 4
DATA GUARD OTN CASE STUDY December 2004 Author: Phil Grice, Joe Meeks, Ashish Ray Oracle Corporation World Headquarters 500 Oracle Parkway Redwood Shores, CA 94065 U.S.A. Worldwide Inquiries: Phone: +1.650.506.7000 Fax: +1.650.506.7200 www.oracle.com Oracle is a registered trademark of Oracle Corporation. Various product and service names referenced herein may be trademarks of Oracle Corporation. All other product and service names mentioned may be trademarks of their respective owners. Copyright 2004 Oracle Corporation All rights reserved.