Open Database RSYNC

[Linus Hicks]

Poe, David wrote:
> We have nearly 200 GB of data in a production Oracle database broken up 
> into about 100 files of 2 GB.  The database incurrs a 5% change per week 
> in the form of new data, no modification nor deletions.  I need to copy 
> this data from one mount point to another then bring up the new database 
> on the new mount point in place of the original.  The high availability 
> and production nature of this system means that my maintenance windows 
> are few and far between.  To minimize my use of the maint window, I 
> would like to pre-copy as much data as I can with RSYNC before the 
> window, then do a final sync of the data during the window with the 
> database down.  My question is, will RSYNC be a good option given that 
> the Oracle database is up and running for the initial sync?

I would suggest you do some experimentation. Remember that rsync will have to 
read both the source and destination files in their entirety in addition to 
doing any writes that are necessary. When source and destination are both on the 
local machine, you may be worse off than just doing a copy.

Try using --inplace on the final rsync. The procedure I wrote specified 
individual files and I think because of that, I had to explicitly use 
--no-whole-file. Don't use -S with --inplace or you will get corruption. Also, 
you might try forcing a checkpoint just prior to your initial copy. You can 
avoid updates to a tablespace by putting it into hot backup mode.

Linus