Oracle Database 11g Direct NFS Clonedb Feature – Part I (and a half).

In Part I of my series on Oracle Database 11g Release 2 Direct NFS Clonedb, I offered short videos with a presentation and a demonstration of the feature. I received a significant amount of email which essentially asked the same few questions. So, instead of answering a bunch of email individually, I’ll address the questions here:

Q. Why is your demonstration modeled around cloning an RMAN backup stored in a file system? All Oracle customers use ASM!
A. I’ve put out Part I as an introduction to the technology. I’ll have more on ASM later. I’m certain that not all customers use ASM. Some might even comment on this post accordingly.

Q. What are the NFS server requirements for the CLONE_FILE_CREATE_DEST?
A. Any NFS mount that supports Oracle Database 11g Direct NFS. Now, this is a bit tricky. Since we are talking about test and development instances I’m not convinced it has to be a commercial-grade filer. After all, the only data that will be stored on NFS with this model is the changed block files (COW) and any new datafiles the test/development instance creates. I have tested on a simple HP Proliant storage server running Linux and exporting NFS shares, but that shouldn’t be misconstrued as a support statement.

Q. What is the My Oracle Support note number mentioned in the Part I?
A. The MOS note is 1210656.1. Keep an eye out for it.

Q. Where can I get the clonedb.pl script?
A. Once the MOS note is online the perl script will be available there. It is just a script that automates a few important tasks and generates SQL (very helpful by the way). I’ll offer a copy at the following link: clonedb.pl

Note, this copy of the script is suitable for clonedb usage with production 11.2.0.2 Oracle. After the performance patch (10403302) is applied this rendition of the script will not work. With that performance patch, the clonedb instance needs to boot with the new init.ora parameter clonedb set to true. The new script will generate the requisite text into the auto-generated clone init.ora.

Q. Does the RMAN backup need to be stored in an NFS mount?
A. No. The copy-on-write/thin-provisioning aspect of the feature is implemented in libodm.so. For this reason the CLONE_FILE_CREATE_DEST assignment needs to be to an NFS mount. That RMAN backup can be elsewhere. More on that later.

Q. What about hot RMAN backups and incremental backups?
A. As I mentioned in Part I, I’ll be going into more detail about such topics as how the snapshot features of commercial NFS filers can augment the Oracle Database 11g Direct NFS clonedb feature. I’ll go over hot backups in that post.

Summary
Folks, thus far the intent was to get introductory materials out so we can all end 2010 thinking about a new way to do something old. I’ve left questions unanswered because, after all, we are only at Part I (and a half) in the series.

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