Setting up raw file system 1

[warburp]

Hi

My Oracle DBA has been doing some anaysis on our Sunfirev880 box running Solaris 8 and Oracle 9. We have redo logs on one of the FCAL disks that has a ufs file system, but to improve performance he has suggested changing just this drive (single mount point) to a raw file system. Not being an experienced sys admin I didn't have a clue what he was on about. After some reading up I have a bit more of a clue but I would appreciate some help:

1. Can you explain what it is /how it works ?
2. How does it differ from ufs?
3. Can you explain how I do it

Thanks

Phil.

 

[daFranze]

when storing data on a disk you are using several drivers, eg. your /oracle/u07 is a ufs filesystem on a SDS striped FCAL RAID, your data goes from the Oracle Structure through the ufs driver, through the SDS driver to the FC driver to the ssd driver; a raw "filesystem" is not a filesystem but (if you think of a single disk) a "raw partition".

If your Oracle DBA want's to use the raw partition foermerly used and mounted on /oracle/u07 it is no big deal to change this. Lookup which device is used in /etc/vfstab to mount it to /oracle/u07; tell your DBA to use this, umount it first and #-out the entry in vfstab; the dba will tell Oracle to use this eg /dev/md/rdsk/d10 as a new place to store data.

The big disadvantage of raw partitions is: it's hard to backup; from a ufs you can get a tar/ufsdump/... backup, the raw partition is only dd able, using OS-commands. You will need to use an Oracle RMAN to backup/restore this.

Best Regards, Franz
--
Solaris System Manager from Munich, Germany
I used to work for Sun Microsystems Support (EMEA) for 5 years

 

[daFranze]

thanks for the star!

Best Regards, Franz
--
Solaris System Manager from Munich, Germany
I used to work for Sun Microsystems Support (EMEA) for 5 years