Kevin Closson's Blog: Platforms, Databases and Storage

While doing an install of 11g x86_64 11.1.0.6 Clusterware today I hit a problem I’ve seen before but had to think for a moment about what was the cause of the error. I figured if I had to scratch my head on this one, someone, someday would likely be out googling for the answer. Here is the error text as it appears in the log:

The location /data/ocr.dat, entered for the Oracle
Cluster Registry (OCR) is not shared across all the nodes in the cluster.
Specify a shared raw partition or cluster file system file that is visible by
the same name on all nodes of the cluster.

In the following screenshot you can see that in the shell at the bottom I first did a chown ora.dba of the nfs directory where I want to locate the OCR file. Clear evidence of cheating. See, when I did that I was able to proceed to the next screen (voting disk). I instead hit the back button on the voting disk screen and changed the ownership of the /data directory just to raise the error and make this quick blog entry. Nice, aren’t I? Anyway, the deal is that this is an error message without an error number erroring erroneously-afterall, the /data directory was in fact shared between the nodes. The problem was that the install precedure uses a write in that directory as evidence of whether it is shared or not. If it isn’t writable it thinks it isn’t shared.