Re: Configure standby EBS 12.1.3 apps server to work with primary database in place

Posted by ErmanArslansOracleBlog on Dec 17, 2019; 7:05am
URL: http://erman-arslan-s-oracle-forum.124.s1.nabble.com/Configure-standby-EBS-12-1-3-apps-server-to-work-with-primary-database-in-place-tp7921p7926.html

If you consider and accept creating the context file and running autoconfig during such a failover, then it is ok.
Basically, you must not touch the database side configuration of that secondary apps node. That secondary apps node should still configured to connect to the primary database, however; it shouldn't connect to the primary during the standby apps tier configuration phase! this is important!

The processes in EBS are mostly dependent to hostname. Having a different IP address is not that much necessary.. you may have minor problems by having a different ip address for the same hostname in your secondary and/or your customization may fail (if they are somehow dependent to the IP address of your apps server) , but generally the effects will be near- zero , or very minor.

*** I mentioned that the effects of having different IP address are minor, but here is the documented method for changing IP address in EBS 11i and R12 environments.. You may consider the actions documented in the document below to your customized failover procedure as well.. ->

Correct Method of Changing the IP Address in 11i & R12 (Doc ID 751328.1)

Yes.. Why not... (can be implemented during failover -- only during your customized failover..)

However; this instruction is dangerous -> "Answer the questions when prompted. This creates your environment files on the application tier. It tries to connect to the database, so some portions will fail, but the environment scripts should be created successfully."

This is dangerous as you will have the same database to connect to.. We don't want any writes to the primary database during your standby apps tier configuration process..

So, what I recommend you is not connect to the primary during your configuration proces.

Just, have the same directory paths and same hostname for the secondary apps tier...
If you can't have the same hostname, then during your failover; just do the following;

Deregister the current Applications server
Create a new Context file
Shutdown the Application Tier Services (already shutdown in your case)
Change the server machine hostname. (already different in your case)
Run autuconfig on apps tier
Start the Applicataion Tier Services

Ref: Apps-Tiers related sections of MOS document "How to change hostname for E-Business Suite Release 12 on single node (Doc ID 1277556.1)"

Remember you will have to do the same thing when you fail back to your original primary...

Test this procedure in your test env and optimize it.
As this is not a standard procedure, the risk is yours!