The ultimate story about OCR, OCRMIRROR and 2 storage boxes – Conclusion

This is a follow-up of chapter 5.
The most important thing in this story is the fact that it is perfectly possible to configure your Oracle RAC cluster with 2 storage boxes in a safe way. You just need an independent location for the 3rd voting disk, but if you have that, you can be sure that your cluster will remain running when one of those storage boxes fail. You will even be able to repair it without downtime after e.g. buying a new storage box (call Uptime for good prices…:)

So were all these tests then really needed? Yes, I do think so, because of the following reasons

  • Seeing that it works gives much more confidence than just reading it in the Oracle doc, or on Metalink
  • The story of the vote count is really interesting. There is (almost) nothing to find about this in the Oracle doc or metalink. With the information in this blog, you will be able to better understand and interpret the error messages in the log files. You will also know better when to (not) update the vote count manually.
  • The concept of OCR master is nice to know. Again, it gives your more insight in the messages in the logfiles.

But apart from these straightforward conclusions, there is one thing I find most interesting. The different scenarios have produced different output, and in one case (scenario 5) even real error messages, allthough they all did the same thing: removing the ocrmirror. With the different scenario’s above, you know why the output can be different. Because if ever you have to handle a RAC case with Oracle support, and you get as reply “we are unable to reproduce your case”, you may now be able to give them more info about what parameter can make a difference (who is ocr master, where is crs stopped, …). Otherwise it can be so frustrating that something fails in your situation and does work in somebody else’s situation.
But now I may be getting too philosophical (which I tend to have after another good “Trappist“)…

Good luck with it!

P.S. And yes, I do have them all in my cellar…

2 Responses to The ultimate story about OCR, OCRMIRROR and 2 storage boxes – Conclusion

  1. odenysenko says:


    Really nice series!

    BTW: there are some formatting issues
    in previous post(fixed font) that make
    them difficult to read…
    it may be related to used WP-template

  2. FUMADOS says:

    Hi ,
    Great job really really interesting !!!
    My only doubt is when you lose both physical access to ocr.
    I have to try it on test environment, but i am not quite sure ocrconfig replace will work and you cannot use a backup since backup will try to use the physical location which is completely lost.
    Do you know how should i recover from backup without using physical old locations of the ocr’s.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: