migration using triple-o method -improved
DESCRIPTION
Triple -O method for oracle migrationTRANSCRIPT
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Migration Using Triple-O Method-By Sripathy Pavan Kumar
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About Triple-O Method:
The Triple-O method is using the O2O technology to
perform the initial data load (copying the current
contents of the source database to the target
database) while the SAP application is up and
running. Oracle Golden Gate is used to synchronize
all changes applied on the source system, while the
migration is running. There are no limitations for the
usage of the SAP system during the migration. Also
heterogeneous database migrations and direct
database upgrades are supported by Triple-O.
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About Triple-O Method:
The Triple-O method is a further development of the
O2O method. This method is certified by SAP to
perform an online migration.
Triple-O method allows to migrate an Oracle
database with a downtime for the database copy of
not more than 15 minutes. The downtime is
independent from the database size. The downtime is
needed to stop the SAP system on the source, check
the final synchronization of the migrated system and
to restart SAP on the target system.
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About O2O Method: Oracle-to-Oracle (O2O) is being used to migrate an SAP
database between different systems.
O2O allows for homogenous and heterogeneous system copies.
O2O supports all operating systems SAP products are certified
on.
O2O supports combination of a platform migration with a
release upgrade.
It is possible to upgrade directly to an higher database release
with O2O.
The downtime needed to migrate a database with the O2O
method is depending on the database size and other factors.
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O2O Architecture:
Large tables >=20 MB are transferred directly over the network using PL/SQL scripts.
Export/Import is done for tables < 20MB. Copy speed is @ 1000GB/Hr.
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About Oracle Goldengate:
Oracle GoldenGate offers a real-time, log-based change data capture (CDC) and replication software platform to meet the needs of todays transaction-driven applications. The softwareprovides capture, routing, transformation, and delivery of transactional data acrossheterogeneous environments in real time. Using this technology, customers can achievecontinuous availability for critical systems and real-time data integration for fast, easy access tocurrent and accurate data.
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Components of OGG
Oracle GoldenGate is composed of the following
components
Extract
Data pump
Replicat
Trails or extract files
Checkpoints
Manager
Collector
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OGG Component overview
ExtractThe Extract process runs on the source system and is the extraction (capture) mechanism of OGG. Data pumpsA data pump is a secondary Extract group within the source OGG configuration. If a data pump is not used, Extract must send the captured data operations to a remote trail on the target. ReplicatThe Replicat process runs on the target system, reads the trail on that system, and then reconstructs the DML or DDL operations and applies them to the target database. TrailsTo support the continuous extraction and replication of database changes, OGG stores records of the captured changes temporarily on disk in a series of files. This Exists on source, Target and Intermediary system. CheckpointsCheckpoints store the current read and write positions of a process to disk for recovery purposes and ensure that they prevent redundant processing. ManagerManager is the control process of OGG and takes care of resource management. CollectorCollector is a process that runs in the background on the target system when continuousonline change synchronization is active.
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How Goldengate works
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Prerequisites for Triple-O SAP Migration:
At least Oracle version 9.2.0.8 on source system.
Target DB version must be on 10.2 or 11.2.
Supplemental logging must be enabled .
OLTP compression must not be used on Source tables to be
replicated but can be enabled for the target.
30% free CPU time in average on database server.
Additional file system space of 50% of the redo log amount in
24h time frame on the source system.
Additional file system space of 50% of the redo log amount in
48h (or the duration of the initial data load) on the target
system.
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Using Triple-O SAP Migration::
There is no downtime needed to start or stop the online
migration.
No need for special database patches.
Migration can be started and stopped at any time
without risk for the productive system.
Downtime needed for the database copy part of the
migration is typically only 15 minutes. The downtime is
independent from the database size.
Triple-O is SAP release independent.
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How Triple-O SAP Migration works:
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Key Steps in Triple-O SAP Migration:
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Key Steps in Triple-O SAP Migration: Run the Oracle Advanced Customer Service (ACS) for SAP O2O (Oracle to Oracle) package
which includes all functionality to create a complete set of migration scripts including a new
source user creation, target database and related tablespace creation, and the OGG source
and target configurations.
Install the Oracle GoldenGate software on source and target
Run the O2O package on the source system
Start GoldenGate change data extract and pump processes on the source system, which will
being capturing and queuing change data and DDL (as needed).Note: All tables in the SAPR3 schema will be included and will contain a SCN/CSN token so that later each table can be filtered by SCN/CSN. A code snippet to add such
as token is:\Table SAPR3.*, Tokens (tk-csn = @GETENV ("TRANSACTION", "CSN"));
Start the initial database load to copy the database objects from the source to target
database.
Validate initial database load.
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Key Steps in Triple-O SAP Migration:
Start GoldenGate replicat apply processes on the target system, which will be
applying captured change data and DDL (as needed). Note: While the replicat process(es) will be started using the AFTERCSN option, tables within a single replicat will be configured to skip transactions based on the table
grouping of the initial loads. This automatically configured by the O2O scripts. Transaction filter by table will be done with something similar to the following code
snippet:\
Map SAPR3.MYTABLE, Target SAPR3.MYTABLE, Filter ( @NUMSTR (@TOKEN ("TK-CSN")) > 1234567);
Switch over. Once both system are in sync the source SAP system may be stopped.
After the last changes is applied to the target the SAP system can be started on the
target system. The source SAP shutdown and target SAP startup will typically take
approximately 15 minutes regardless of the system size.
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Summary:
Triple-O and O2O are well established
methods which offers a fast and reliable
approach, not only to migrate a SAP database
from any SAP supported OS platform from
Oracle Database 9i Release 2 on, to the Oracle
Exadata Database Machine, but also to
implement a couple of additional features and
benefits into the migration process.
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Additional related information:
About Oracle Exadata Database Machine:
The Oracle Exadata Database Machine (OEDM) is used for
storing the databases of the individual SAP systems.
The OEDM cannot be used for SAP Instances and run on
Oracle Solaris 11 Express or the Oracle Linux 5 operating
system.
BR Tools and Central services can used on OEDM.
Only DB Migration from a existing system is supported by
OEDM.
SAPINST for DB on OEDM is supported from version 7.0 EP 3
and 7.3 EP 1.(Refer Note 1619343)
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Reference: Oracle GoldenGate Installation and Setup Guide
Oracle GoldenGate Administration Guide
Oracle GoldenGate Reference Guide
Oracle GoldenGate Troubleshooting and Performance Tuning Guide
Oracle GoldenGate Tutorial guide
SAP Note 1508271,1619343