Most people think of Data Guard as a disaster recovery solution, and it certainly excels in that role. However, did you know that you can also use Data Guard for platform migration under some conditions?
While you would normally have your primary and standby Data Guard systems running on the same OS and hardware platform, there are some heterogeneous combinations of primary and stanby system that are supported by Data Guard Physical Standby.
One example of heterogeneous Data Guard support is the ability to go between Linux and Windows on many processor architectures. Another is the support for environments that are running HP-UX on both PA-RIsC and Itanium hardware. Brand new in 184.108.40.206 is the ability to have both SPARC Solaris and IBM AIX on Power Systems in the same Data Guard environment. See My Oracle Support note 413484.1 for all the details about supported platform combinations.
So, why mention this in an upgrade blog? Simple: much of the time required for a platform migration is usually spent copying files from one system to another. If you are moving between systems that are supported by heterogeneous Data Guard, then you can reduce that migration downtime to a matter of minutes. This can be a big win when downtime is at a premium (and isn’t downtime always at a premium? In addition, you get the benefit of being able to keep the old and new environments synchronized until you are sure the migration is successful!
A great case study of using Data Guard for a technology refresh is located on this OTN page. The case study showing CERN’s methodology isn’t highlighted as a link on the overview page, but it is clickable.
As always, make sure you are fully versed on the details and restrictions by reading the available documentation and MOS notes. Happy migrating!
We are migrating E-biz R12 to itanium platform from RISC. Wondering wheather we can utilize data guard to minimize downtime ? is it possible?
Your help much appriciated !
It may very well be possible to use heterogeneous data guard to minimize downtime for such a migration. The key is to look at MOS note 1079563.1, which gives the version numbers for which RMAN is able to instantiate a physical standby cross-platform.
In the case of the PA-RISC to Itanium pair, your database would need to have been CREATED as Oracle Database 10g Release 2 or later. As note 1079563.1 says, if the database was created with an earlier version and upgraded to 10.2 or later, then an RMAN CONVERT is still required — which means that heterogeneous data guard would not work.
What is the quickest and safest way to migrate a 50+Tb database hosted on Solaris 64-bit Sparc to an Oracle Linux x86 environment
Transportable Tablespaces with RMAN Incremental Backups – and depending on your versions potentially Full Transportable Export/Import with Inc Backups.
In the case where we have a primary database running in Windows and the Data Guard in Linux (this is a permanent Data Guard not for migration) how do we apply RU patches in Linux and Windows Bundle patch in primary? I think it is impossible since Windows and Linux patches are not the same, not even similar correct? And the datapatch step if we run in Windows it will be replicated to Linux, Linux wont have RU datapatch applied because it is a standby.
the patch content should be identical – but you are right, there may be differences. Still I don’t think that this will cause an issue WHEN you make sure that you run “datapatch” after activating the standby. But it is a very valid question.
I need to migrate Oracle 11g from AIX to RHEL is this good using dataguard or doing an export and then applying incrementals and is there an oracle note on this
sorry for my late reply – I’m far behind with answering comments on the blog.
You can’t use DG since there is no cross-Endianness Data Guard available. You could go from Windows to Linux (both Little Endian platforms) or from AIX to SPARC (both Big Endian) but not from AIX (Big) to Linux (Little). You can either use Data Pump or Transportable Tablespaces / Full Transportable Export Import.