9.15.2008

My experience of converting a cross platform (AIX to HP) single instance database to RAC using RCONFIG tool

Its been really more than a month that I didn't write anything on my blog due to my busy schedule.  Well, I am here now to share my experience of converting a cross platform (AIX to HP) single instance database to 2 node RAC using the RCONFIG tool.

If you were following my blog, you might aware that we have a plan of implementing 16 node production RAC on HP UX Superdom Itanium servers using EMC DMX4 SAN storage. 
As part of production implementation, last week, I have configured initial 8 node RAC successfully and the immediate plans were to migrate the databases across operating systems (AIX to HP ux) and convert a single instance database to RAC. I have done this exercise on the development setup sucessfully, the only change this time is that I have used RCONFIG utility to convert single instance database to RAC. Earlier I have used DBCA method to do the same.

Oracle provides following methods to convert a single instance database to RAC:

Grid Control
DBCA
Manual
RCONFIG(from 10gR2)

I must say, each DBA may choose a different method according to his/her convineance to achieve the result. The following illustrates how I have migrated a database from AIX to HP UX and from a single instance to RAC (on 2 node).

Database and OS details

Source:

Database 10gR2 (10.2.0.4)
OS : AIX
non-ASM

Target:

Databae 10gR2 (10.2.0.4)
OS : HP UX Superdom Itaninum
ASM

RCONFIG brief
RCONFIG tool is introuced in Oracle 10gR2 and the main functionality of this tool is to convert single instance database to RAC. 
The tool(rconfig) can be found under $ORACLE_HOME/bin directry.
The xml input file (ConvertToRAC.xml) resides under $ORACLE_HOME/assistants/rconfig/sampleXMLs (it is recommended to copy the file before using it).
Log files(rconfig.log and etc) can be found under $ORACLE_HOME/cfgtoollogs/rconfig

The Convert verify option in the ConvertToRAC.xml file has three options:

  • Convert verify="YES": rconfig performs checks to ensure that the prerequisites for single-instance to RAC conversion have been met before it starts conversion
  • Convert verify="NO": rconfig does not perform prerequisite checks, and starts conversion
  • Convert verify="ONLY" : rconfig only performs prerequisite checks; it does not start conversion after completing prerequisite checks 

Before you actually starts the convert process, you can run the rconfig with convert verify=ONLY option which basically check all the prerequisites. At the end, the result code either would be 0 or 1. Where 0 stands for operation success and 1 stand for operation failures and in case of failure, it will also gives you the reason of failure.

Following RMAN command converts the database from AIX to HP UX platform.

RMAN> convert database new database 'ORCL'

 transport script '/tmp_backup/tempdb/transport.sql'

 to platform 'HP-UX IA (64-bit)'

 db_file_name_convert

'+DG_ORCL/ORCL/datafile','/tmp_backup/tempdb';

Move all the converted datafiles to target machine and follow the ML NOTE: 414878.1  for further details on how to start the on target machine.

Following illustrate how to convert single instance database to RAC using the RCONFIG tool:

cp $ORACLE_HOME/assistants/rconfig/sampleXMLs/ConvertToRAC.xml convertdb.xml

modify the convertdb.xml file according to your environment. Following is the example:

==
convert_t24uat.xml 46 lines, 2964 characters 
 ?xml version=1.0 encoding=UTF-8?
 RConfig xmlns:n=http://www.oracle.com/rconfig
           xmlns:xsi=http://www.w3.org/2001/XMLSchema-instance
           xsi:schemaLocation=http://www.oracle.com/rconfig
    ConvertToRAC
  Verify does a precheck to ensure all pre-requisites are met, before the conversion is attempted. Allowable values are: YES|NO|O
NLY
        Convert verify=NO
 Specify current OracleHome of non-rac database for SourceDBHome
              SourceDBHome /u00/app/oracle/product/10.2.0/db_1 SourceDBHome
 Specify OracleHome where the rac database should be configured. It can be same as SourceDBHome
              TargetDBHome/u00/app/oracle/product/10.2.0/db_1 TargetDBHome
 Specify SID of non-rac database and credential. User with sysdba role is required to perform conversion
              SourceDBInfo SID=ORCL
                Credentials
                  User sys User
                  Password password Password
                  RolesysdbaRole
                Credentials
              SourceDBInfo
 ASMInfo element is required only if the current non-rac database uses ASM Storage
              ASMInfo SID=+ASM1
                Credentials
                  User sys User
                  Password passwordasm Password
                  RolesysdbaRole
                Credentials
              ASMInfo
 Specify the list of nodes that should have rac instances running. LocalNode should be the first node in this nodelist.
              NodeList
                Node name=rac01
                Node name=rac02
              NodeList
 Specify prefix for rac instances. It can be same as the instance name for non-rac database or different. The instance number will be attached to this prefix.
              InstancePrefix ORCL InstancePrefix
 !--Specify port for the listener to be configured for rac database.If port=, alistener existing on localhost will be used for rac
 database.The listener will be extended to all nodes in the nodelist --
              Listener port=""
 Specify the type of storage to be used by rac database. Allowable values are CFS|ASM. The non-rac database should have same storage type.
              SharedStorage type=ASM
 Specify Database Area Location to be configured for rac database.If this field is left empty, current storage will be used for rac database. For CFS, this field will have directory path.
                TargetDatabaseArea+DG_ORCL TargetDatabaseArea
 Specify Flash Recovery Area to be configured for rac database. If this field is left empty, current recovery area of non-rac dat
abase will be configured for rac database. If current database is not using recovery Area, the resulting rac database will not have
a recovery area.
         TargetFlashRecoveryArea +DG_ORCL Target FlashRecoveryArea
        SharedStorage
        Convert
     ConvertToRAC
 RConfig

===
Once you modify the convert.xml file according to your environment, use the following command to run the tool:

rconfig convertdb.xml

Oracle does the following during conversion:
oracle@usogp01: /u00/app/oracle/product/10.2.0/db_1/bin # ./rconfig convertdb.xml
Converting Database ORCL. to Cluster Database. Target Oracle Home : /u00/app/oracle/product/10.2.0/db_1.
Setting Data Files and Control Files
Adding Database Instances
Adding Redo Logs
Enabling threads for all Database Instances
Setting TEMP tablespace
Adding UNDO tablespaces
Adding Trace files
Setting Flash Recovery Area
Updating Oratab
Creating Password file(s)
Configuring Listeners
Configuring related CRS resources
Adding NetService entries
Starting Cluster Database
Starting Listeners
    
      
        
          Operation Succeeded
        
      
      
         /u00/app/oracle/product/10.2.0/db_1
      
        
          ORCL1<\SID>
          ORCL2<\SID>
        <\SIDList>    
    
  
oracle@usogp01: /u00/app/oracle/product/10.2.0/db_1/bin #

==
As you can see the exit code is 0, which indicates the success of the conversion process.


Uphills faced during the conversion process

The only error which I got during the conversion was missing listener.ora under ORACLE_HOME/network/admin directory as we had created listener under the ASM home (we have separate RDBMS and ASM homes). Problem has been resolved by creating the link under the RDBMS network admin directory of ASM listener.ora file.

We have contacted one of the developer of rconfig utiity to clarify the two changes (following) to make sure it will work:

non-ASM to ASM 
single instance to RAC.

He said that the main purpose of this utility is to convert single instance database to RAC and optinally few non-ASM of target database to ASM while converting to RAC. But, he is not sure about moving the entire non-ASM to ASM while conversion. As they don't have any test case. However, asked us to go ahed and try. Well, we were amazed that it worked for us and we delightly informed the developer that two changes are worked for us and you can have our reference.

Our next migration/conversion is our EBusiness suit and of course, I am going to share my expereince here.

References

http://download-west.oracle.com/docs/cd/B19306_01/install.102/b14201/cvrt2rac.htm#sthref1273


Important Meta Link Notes:

ML Note:387046.1 RCONFIG : Frequently Asked Questions
ML Note:371519.1 RCONFIG Error When Converting From Single Instance To RAC
ML Note:375472.1 RCONFIG FAILS with an null pointer EXCEPTION
ML Note:391297.1 RCONFIG fails when using ASM as Shared Storage
ML Note:388577.1 Using Oracle 10g Release 2 Real Application Clusters and
 Automatic Storage Management with Oracle E-Business Suite 
 Release 12


Happy Reading,

Jaffar

5 comments:

overmars said...

RMAN> convert database new database 'ORCL'
transport script '/tmp_backup/tempdb/transport.sql'
to platform 'HP-UX IA (64-bit)'
db_file_name_convert
'+DG_ORCL/ORCL/datafile','/tmp_backup/tempdb';

this command means convert an ASM database on AIX to filesystem on HPUX?

Alberto said...

Hi....

It's possible migrate with transportable tablespace Oracle 8.1.7.4 (True64) to 10.2.0.4 (Aix 5L)?

Thanks.
Alberto

The Human Fly said...

Alerto,

Cross platform tts feature was introduced with 10gR1 and Cross platform database transport feature add with 10gR2. Therefore, I don't think your task is achievable.

Jafar

The Human Fly said...

Overmars,

The example which I have shown here will convert the database to AIX OS, irrespective of your source db OS.

Jaffar

DanyC said...

Very interesting task & article.

Nice one Jafar.

Thanks,
Dani