RACONENODE : convert your rac database to active/passive

Configuring RACONENODE in RAC database.

We all know that Oracle RAC is active/active configuration, but due to application compatibility (the design part like cache fusion incompatibilities etc) you will need to stick to active/passive configuration but you want High availability solution and you do not want to use any third party clustering like VCS, Answer is yes, use raconenode feature. Here are the steps for the same.

You can also use the service level restriction stick to one node by specifying preferred and available nodes, the following is works exactly as service level but the second node is always passive which can reduce the overheads of cache fusion since your application is not compatible, like you have lots of reads from both nodes on single block which may lead to contention for buffer busy waits.

a) Check Status of RAC database

	[RACDB1@Geek DBA-rac1 ] $srvctl status database -d RACDB
	Instance RACDB1 is running on node Geek DBA-rac1
	Instance RACDB2 is running on node Geek DBA-rac2

b) Keep one of the instance down before converting database to one-node RAC configuration.

	[RACDB1@Geek DBA-rac1 ] $srvctl stop instance -d RACDB -i RACDB2

c) Keep one of the instance active in Cluster before converting database to one-node RAC configuration.

	[RACDB1@Geek DBA-rac1 ] $srvctl convert database -d RACDB -c RACONENODE -i RACDB1
	PRCD-1214 : Administrator-managed RAC database RACDB has more than one instance

	The above error means you should have only 1 Instance of Database running and active for converting it to One-Node RAC.

	[RACDB1@Geek DBA-rac1 ] $srvctl remove instance -d RACDB -i RACDB2
	Remove instance from the database RACDB? (y/[n]) y

d)It is mandatory to have at-least one service active for given instance before you convert it into RACONENODE mode, else you will get error.

	[RACDB1@Geek DBA-rac1 ] $srvctl convert database -d RACDB -c RACONENODE -i RACDB1
	PRCD-1242 : Unable to convert RAC database RACDB to RAC One Node database because the database had no service added

	[RACDB1@Geek DBA-rac1 ] $srvctl add  service -d RACDB -s TEST -r RACDB1

e) Use srvctl convert command to change your database from RAC mode to RACONENODE.

	[RACDB1@Geek DBA-rac1 ] $srvctl convert database -d RACDB -c RACONENODE -i RACDB1

f) Verify One Node RAC configuration.

	[RACDB1@Geek DBA-rac1 ] $srvctl config database -d RACDB
	Database unique name: RACDB
	Database name: RACDB
	Oracle home: /u01/app/oracle/product/11.2.0/db_1
	Oracle user: oracle
	Spfile: +ASMDATA/RACDB/spfileRACDB.ora
	Domain:
	Start options: open
	Stop options: immediate
	Database role: PRIMARY
	Management policy: AUTOMATIC
	Server pools: RACDB
	Database instances:
	Disk Groups: DATA, FRA
	Mount point paths:
	Services: TEST
	Type: RACOneNode    <<<<<<< The database has successfully turned into 1-Node Configuration.
	Online relocation timeout: 30
	Instance name prefix: RACDB1
	Candidate servers: Geek DBA-rac1
	Database is administrator managed

g) In case you want to relocate a RAC 1-Node database from 1 node to another, you can use following syntax

	[RACDB1@Geek DBA-rac1 ]srvctl relocate database -d RACDB -n Geek DBA-rac2 

Geek DBAGeek DBA