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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Veritas CFS or QFS ? Which for High Hybrid Transaction Load Benchmark on RAC with Solaris 10/Oracle 10g ?
ALL CAPITALS is hard to read...
Yes, you can use dd for moving your cooked files onto raw devices. A a raw device is just like any other file, you don't need any RMAN magic to get your files on these.
However, you must be aware of how much space does Oracle reserve in beginning of the datafile (before datafile header) for cooked filesystems and for raw. This varies between platforms.
I'd create a small tablespace onto filesystem and another one directly to
raw device - then I'd attach to CKPT process with truss and issued a
checkpoint.
As checkpoint happens truss should report into what offset is CKPT doing its
write - in other words in which block from start of the file the datafile
header resides (yes, the datafile header doesn't reside physically in the
first block of a datafile. It's often the 2nd one).
Anyway, if the amount of reserved blocks is the same between raw and cooked, then you can just blindly dd your datafiles onto raw devices. If the raw offset differs from cooked, then you have to adjust your dd parameters to match raw offsets.
Tanel.
From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]
On Behalf Of VIVEK_SHARMA
Sent: Thursday, August 31, 2006 18:46
To: Zhu,Chao
Cc: oracle-l_at_freelists.org
Subject: RE: Veritas CFS or QFS ? Which for High Hybrid Transaction Load
Benchmark on RAC with Solaris 10/Oracle 10g ?
Thanks Zhu for the info & replies
Some Questions are IN CAPITALS BELOW:-
From: Zhu,Chao [mailto:zhuchao_at_gmail.com]
Sent: Thursday, August 31, 2006 2:08 PM
To: VIVEK_SHARMA
Cc: oracle-l_at_freelists.org
Subject: Re: Veritas CFS or QFS ? Which for High Hybrid Transaction Load
Benchmark on RAC with Solaris 10/Oracle 10g ?
Simply use rman to restore your datafiles to raw volumes. OK
The most min-downtime solution is;
build a standby on the raw volume on rac, do a switch over, and your
databsae is running in rac mode within 10 minutes.
THERE ARE NO TIME CONSTRAINTS AS NO PRODUCTION DATABASE IS INVOLVED. THE AIM IS TO CHECK THE POSSIBILITY OF CONVERTING A BIG BENCHMARK DATABASE CURRENTLY EXISTING ON A MOUNTED "UFS" FILESYSTEM "TO" RAW DEVICES WITHOUT USING EXPORT/IMPORT & RMAN. You can take anytime you desire to make your standby database onto the raw volume.
IS IT POSSIBLE IN SOME MANNER TO COPY THE DATAFILES FROM THE SOURCE DATABASE EXISTING ON MOUNTED "UFS" FILESYSTEM PARTITIONS "TO" THE TARGET DATABASE EXISTING ON PRE-CREATED RAW DEVICES FOR THE 1st TIME FOR THE CREATION OF THE STANDBY DATABASE? CAN "dd" COMMAND BE USED?
Thanks
-- http://www.freelists.org/webpage/oracle-lReceived on Thu Aug 31 2006 - 08:52:27 CDT
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