In earlier May 2020, we heard of high availability option for Standard Edition2 databases.

"Standard Edition High Availability provides cluster-based failover for single-instance Standard Edition Oracle Databases using Oracle Clusterware. " https://blogs.oracle.com/maa/standard-edition-high-availability-officially-released

I tried it how it works in my virtualbox environment, here is my feedback to you.

You need to have installed Grid Infrastructure and Single Instance Oracle database on the first node of cluster. You must store the Oracle Database binaries only on local storage or Oracle ACFS volume to enable the Oracle Database Standard Edition High Availability feature. There are lots of basic requirements here.

To configure acfs, run ASMCA, then create a diskgroup and create acfs.

After your Oracle Clusterware (grid) configuration, you need to install oracle database on the first node of cluster, make sure you choose "Single instance database installation" and "Standard Edition 2" from wizard.

I choose to install ORACLE_HOME on local and ORACLE_BASE on acfs storage, as described in official guide. Don't worry, everything is in following gif.

Then add your remaining Oracle homes to the first node using below:

[oracle@vrac1 ~]$ $ORACLE_HOME/bin/roohctl -enable
[oracle@vrac1 ~]$ $ORACLE_HOME/addnode/addnode.sh CLUSTER_NEW_NODES=vrac2InstallOracle_2ndNode

After the Oracle Database software installation is complete, use DBCA to create a Standard Edition database on the first cluster node on which you installed the Oracle Database software.

Now it's time to enable SEHA. Follow guide in official document, see below for how I did:

[oracle@vrac1 ~]$ srvctl add database -db acfsdb -oraclehome $ORACLE_HOME -dbtype SINGLE -spfile +DATA/ACFSDB/PARAMETERFILE/spfile.276.1040861431 -node vrac2

[oracle@vrac1 ~]$ srvctl modify database -db ACFSDB -node vrac1,vrac2

[oracle@vrac1 ~]$ srvctl config database -db ACFSDB
Database unique name: acfsdb
Database name: acfsdb
Oracle home: /home/oracle/19/dbhome_1
Oracle user: oracle
Spfile: +DATA/ACFSDB/PARAMETERFILE/spfile.276.1040861431
Password file: +DATA/ACFSDB/orapwacfsdb
Domain: bitofcloud
Start options: open
Stop options: immediate
Database role: PRIMARY
Management policy: AUTOMATIC
Server pools:
Disk Groups: DATA
Mount point paths: /acfs
Services:
Type: SINGLE
OSDBA group: dba
OSOPER group: oper
Database instance: acfsdb
Configured nodes: vrac1,vrac2
CSS critical: no
CPU count: 0
Memory target: 0
Maximum memory: 0
Default network number for database services:
Database is administrator managed

You can confirm that vrac1 and vrac2 are now configured for database ACFSDB.

Now let's see how to relocate running instance from vrac1 to vrac2 instance using below command:

[oracle@vrac1 ~]$ srvctl status database -db ACFSDB

Instance ACFSDB is running on node vrac1

[oracle@vrac1 ~]$ srvctl relocate database -db ACFSDB -node vrac2

[oracle@vrac1 ~]$ srvctl status database -db ACFSDB

Instance ACFSDB is running on node vrac2

Or maybe you'd like to see recording of switching to another node:

Finally, the most important note from me is, you must configure your patch level to 19.7 in Database and Clusterware, then you can install Oracle Database Standard Edition 2 in high availability mode.

If you start SE2 high availability without 19.7 patch, you will stuck for few days to dig down the errors, just like how I did :) , believe me I spent stupid amount of time on this, because of this.

[grid@vrac1 OPatch]$ ./opatch lspatches
30898856;TOMCAT RELEASE UPDATE 19.0.0.0.0 (30898856)
30894985;OCW RELEASE UPDATE 19.7.0.0.0 (30894985)
30869304;ACFS RELEASE UPDATE 19.7.0.0.0 (30869304)
30869156;Database Release Update : 19.7.0.0.200414 (30869156)

[oracle@vrac1 OPatch]$ ./opatch lspatches
30894985;OCW RELEASE UPDATE 19.7.0.0.0 (30894985)
30869156;Database Release Update : 19.7.0.0.200414 (30869156)

Conclusion?

Well, it's not a RAC guys, and also 10 days of rule will apply, so there's a catch. But, I am amazed by SE2 is now have high availability and you can easily do failover within clusterware and benefit from the cluster capabilities and storage solutions with lot cheaper EE.

Enjoy and benefit from this high availability in SE2!

Original post by me:

Standard Edition High Availability
In earlier this month, we heard of high availability option for Standard Edition2 databases. “Standard Edition High Availability provides cluster-based failover for single-instance Standard Edition Oracle Databases using Oracle Clusterware.