Tuesday, July 04, 2006

How to convert a single instance database to a RAC database

There are multiple ways in Oracle 10gR2 to convert a single instance database into a
clustered database.
You can use the following methods to do this:
- dbca
- enterprise manager
- rconfig utility (new in 10gR2!)

After you have checked if your operating system requirements are met you can choose either of these methods to do the conversion.
You should make sure first that your hardware and operating system are supported.
To do so you check with your hardware vendor and for the platforms you check metalink.

Once this is done you go on with either methode:
- dbca does most of the tasks of the conversion automatically
- grid control provides fully support the conversion process
there is a very nice demo for this in the OBE (Oracle By Examples demos for RAC 10gR2 section)
- new with 10gR2 there is utility called rconfig which is located in $ORACLE_HOME/bin.
It uses a file called $ORACLE_HOME/assistants/rconfig/sampleXMLs/ConvertToRAC.xml which you need to edit in order to adjust some parameters as needed and then save it under a new name. It contains the parameter for the Convert verify option which accepts three different values:
CONVERT VERIFY= "YES" -- performs checks to make sure everything is in place before starting the conversion
- "NO" -- starts conversion right away without checking the prerequisits
- "ONLY" -- only performs the prerequisits-check

You then call the utility and hand over your modified xml file:
$ rconfig my_db_conversion_file.xml


At Tue Jul 04, 06:29:00 PM, Blogger Alex Gorbachev said...

Thanks Lutz. I wasn't aware of rconfig.
By the way, you forgot to mention the method number four - the good old manual way. ;-)

Now Oracle needs to include wizard alike one step action to convert single non-RAC installation of Oracle home to a multiple nodes RAC Oracle home including CRS. This would be the killer wizard if it work!

At Wed Jul 05, 01:31:00 PM, Blogger lutz_hartmann said...

Hi Alex, did you have a look at the demos on OTN? Maybed there are some interesting things for you. Lot's of 10gR2 RCA New Features demos available there.

At Fri Jul 07, 08:36:00 PM, Blogger Alex Gorbachev said...

Yep there are useful examples (and thank you for referencing OBE first time in your blog). They are useful because they give good directions on common tasks. However, real life situations often are bit different and exact steps might be to some degree different.
The case I described (non-RAC to RAC installation) is one of them - most of the time requirements and environment are so different that there is no common bulletproof path that can be "wizardized" but rather recommendations so I was kidding. Anyway, that's why we have experienced DBAs. Isn't it? ;-)

At Mon Sep 04, 09:32:00 AM, Blogger Sandeep said...

I have used "rconfig" to convert the Single Instance 10g R2 DB to RAC. It works like a charm !! Even when there is a failure at 95% completion & you start all over again ..it cleans up everything & starts the process again !!



Post a Comment

<< Home