A couple of weeks ago I posted about doing a fresh installation of Enterprise Manager Cloud Control 13c (article, blog post). I’ve finally got around to doing an upgrade test from EM CC 12cR5 to 13cR1. You can see the result of that here.
As you’ll see from the article, the upgrade process was similar to the patches that came before it. There are of course some extra prerequisites which you can read about in either my post, Gokhan’s or the docs…
Even though the upgrade tests were fine, after discussion with our system administrators, we are probably going to go for a clean installation and migrate the monitored hosts one at a time.
Why the slash and burn approach? I’ve made some mistakes with our installations in the past and they persist with every subsequent upgrade. It would be nice to take a step back and fix stuff. We are doing a similar thing with our WebLogic installations. I was learning new stuff all the time while I was installing our WebLogic 11g infrastructure. Rather than upgrading to WebLogic 12cR2, we are going to build a new infrastructure, migrate to it and throw the old one away.
This is relatively easy for us for a few reasons.
- We use virtualization for everything. We will provision the new VMs, set everything up. Start migrating stuff. When the migration is complete we will throw away the old VMs. No major hardware overhead.
- We are a pretty small operation. If we had a massive amount of infrastructure, a slash and burn approach would be very time consuming and as such, very costly.
- I am really anal about some things and I am willing to go the extra mile to get things right. I did the best I could at the time, but I’m happy to admit I made mistakes and I want to sort them out. This is not because I’m a company boy. It’s because those mistakes eat away at me and I want them eradicated so they will only haunt me in my memories, not in my day to day life.
If we had been going for the upgrade approach, I probably would have done it in the next couple of weeks. With clean slate approach, we’ll probably take a few more weeks to get ready for it. No point rushing in and making more mistakes. I would rather let the idea brew for a while before we start.