Oracle 12.2 GI infrastructure
Oracle 12.1 Database as Primary with two instances as RAC
Oracle 12.1 Database as Physical Standby database with a single instance on Oracle Restart - ASM
This is what customer consider as an option for DR and I am not going to comment!
ORA-16598: Oracle Data Guard broker detected a mismatch in configuration
Purpose of this post is to share how you can debug ONS - FAN events notification if you need to setup Weblogic / Data Source to be aware of the ONS FAN events
ONS is a very useful option if you are using Oracle RAC architecture but the prior actual configuration of GridLink in the Weblogic make sure that your ONS working from the local and remote side because it may lead to an issue in the Weblogic and high CPU utilization
Also, check Metalink for a bug related to the jdbc driver and ONS feature because it may require to patch Weblogic prior to implementing it.
Please check the below reference link in order to get familiar with ONS and what has been changed in 18c compared to 12c
After a lot of work today, i try to get some time to share very short finding which is very useful in order to prevent the max process on ASM instance.
There was an issue with one of the newly created Oracle GI 12c - 18.104.22.168 due to massive migration and ASM instance report error ORA-00020: maximum number of processes. This problem lead to a lot of unnecessary communication for downtime in order to fix ASM instance by adding more processes :)