DR setup for ebs

[satish]

Dear erman,

Below is the architecture of prod

2 node application tier—- Shared application tier file system(Rhel GFS cluster) R12.2.5
2 node database tier—-Rac 12.1.0.2
A software load balancer..

We are planning to set up DR.

Do we need any licences from oracle,Rhel to do this setup?Any idea

Thanks,
Satish

[ErmanArslansOracleBlog]

Yes.

You have to license the DR site as well.. Oracle licenses are required.
Talk with your Oracle sales representative..

[satish]

Sure erman.Infrastructure team said they cannot provide similar existing configuration for dr with respect to number of servers.

So,our primary will be rac 2 node and dr will be single node.
Same with application tier.Will we have any issues with that.Have u seen any configuration like this.

Thanks,
Satish

[ErmanArslansOracleBlog]

No technical issues. Technically it is possible.
But your company should decide that. It depends on your policy.
So when you failover to DR , you will have both decreased high availability and decreased computational resources.. If it is ok for you , then that 's fine.

[satish]

Thanks erman.

Whatever patches we apply in primary, do we need to apply the same patches to dr as well(in case of oracle homes, both db and application)

Thanks,
Satish

[ErmanArslansOracleBlog]

You can sync both the db and apps tier.
Patching is another subject.
You need to follow the best practices for that.
Normally when you patch the database, the patched in-db things are transferred and applied to the standby/DR database.. Similary, in apps tier, when you patch the things the relevant synchronization mechanism of your synchronize the DR apps tier.. But! patching should be done by following the best practices.. You need to implement methods to guarantee the failback in case of a patch failure.. To do that, you got to take prior actions like stopping the synchronization before patching and then starting it after the sucessful patch application.. (to ensure the standby guarantees the failback in case of patch failure)
We also have a method called standby-first patching..

Well, you need to  develop a Patch Strategy and Plan Ahead.

Actually, you got to read some document about it.

For instance one scenario for the db tier can be the following;

Disable redo transport on primary
shutdown the standby and apply the patches to the binaries on it. (you don't take post upgrade actions as they will be done once you patch the primary.. they will be transported from there..)
shutdown the primary and apply the patch
start the primary
Enable redo transport.
Start MRP on standby.

In another scenario , you can do the following;

Ensure standby database is in sync with the primary database.
Stop redo transport from primary database.
Stop recovery on the standby database.
Shutdown the primary database and apply the patch (including the post steps)
Shutdown the standby site and patch the binaries.
Mount the standby database.
Start redo transport from primary database.
Start recovery on the standby database.

[satish]

Thanks erman..similarly any steps or  process to sync application tier

[ErmanArslansOracleBlog]

Yes. Basically you will sync the apps tier as well.. You will do it by using a file based synchronization mechanism or a storage based (snapshot, snapmirror etc..) mechanism..
Again, you will do it intelligently.. You will sync the directories that are changing frequently all the time, if you like.. Binaries are normally not changed during the day, so you may sync them only in certain events like patching, doing configuration changes and etc..

In fact you can read MOS to get the idea,

for instance : Business Continuity for Oracle E-Business Suite Release 12.2 Using Oracle 12c (12.1.0.2) Physical Standby Database (Doc ID 1963472.1)