EBS upgrade 12.1.2 to 12.2.9 and DB upgrade to 19c

[soumya]

Dear Erman,

Hope you are doing well. First of all thanks for all the handwork you are putting through the forum. Really appreciated.

We have a situation where customer would like to upgrade their existing ebs 12.1.2 to ebs 12.2.9 and their db from 11.1.0.7 to 19c. Customer's db size is 1.8TB

They have asked for a plan for the entire upgradation.

I have a few questions regarding the same.
1.Is it recommended to go for entire upgrade (both DB and APP) in a one go? Or is it better to go for DB upgrade first and once things seem good, going ahead with application upgrade later ?

2.They have proposed 24hrs downtime. I know it is dependent on many factors, however do you think its feasible to to manage the entire activity in 24hrs?

3.Would like to know the migration path for DB and APP tier.
Do we need to upgrade from 12.1.2 to 12.1.3 and then go for 12.2 ? OR we can directly upgrade from 12.1.2 to 12.2

4.In this upgrade scenario , how would you prepare for a fallback strategy in case something goes wrong ?

5.Would to hear your personal experience regarding the 12.2.9 upgrade along with 19c if like to share.


Hope to hear from you.

Thanks for all the effort once again.

Soumya  Das

[ErmanArslansOracleBlog]

Hi Soumya,

In one go?  It is a little risky and your downtime will be longer.
Your DB version is too low. You can't make a direct upgrade from 11.1.0.7 to 19C.. Your db should be 11.2.0.4 at least.
EBS 12.1.2 is not certified with DB 19C, but you can upgrade it to EBS 12.2 directly.

So I would first upgrade the database to a DB release that is directly upgradable to DB 19C.

Your plan should be;

1)Upgrade your DB to 11.2.0.4 ( EBS 12.1.2 is certified with it)
2)Upgrade your EBS 12.1.2 to 12.2 (direct upgrade supported)
3)Upgrade your 11.2.0.4 DB to 19C  (direct upgrade supported)

You can combine 2nd and 3rd actions together and do it in one go , but I don't recommend that..
2nd operations is already a complex one, so you need to concantrate well..

Upgrade duration may change due to lots of things.. (your db size, your compute power and so on)
You need to test it well.. (at least 2 iterations for DB upgrades, and at least 3 iterations for EBS upgrade)

FAilback plan should be ready, tested and documented for all the steps of all the operations.
You need to create your upgrade plan, upgrade strategy, failback plans, SOPS and even a run book..
That upgrade should be managed well in terms of project management as well..

[soumya]

Thanks Erman for the insights.

Much appreciated.

Soumya

[soumya]

Hi Erman,

I have another query for you.

Does this kind of upgrade specially from 12.1.2 to 12.2.9 incur any major functional changes  for any module in EBS?

Thanks,
Soumya