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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Raw Vs. File systems, your opinion?
Hmmm dont you love a good religious war every now and again.
Having administered about six oracle parallel server clusters for over a
year now, Ive changed my opinion completely on raw devices - now I prefer
them.
It is easier to see file and volume layouts for databases with complex
layouts using Veritas Volume manager's (very nifty) gui. I also get
considerable peace of mind knowing that there are no database files that
can be deleted at the filesystem level : in the past I've had several unix
administrators screwing up my databases by overmounting a filesystem, or
something similar.
No such problems with raw partitions : you are less likely to get
accidental or malicious damage to a critical database if it is raw, imho.
Backups are more complex, but generally only larger sites consider raw
partitions, and subsequently have purchased an enterprise level backup tool
that handles raw partitions as easily as files.
An aside : for sites that use dedicated redo disks, and put two or three redo log files on each dedicated disk pair : is there any reason not to create more redo groups (say 10) on the same two disk pairs, so that online recovery, if it is required, is less likely to need archive logs to be pulled from tape? It is a better use of the redo pairs than having an online archive log bucket filesystem. Since redo log files are not hot-backedup their total size doesnt matter. Comments?
Regards
Mark
Perth, Australia
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