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<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2>We're using RMAN to
back up our 9.2 RAC database to an OCFS v1 volume. We have an existing shell
script that we use for copying files from disk to tape via tar, one file at a
time. (Don't ask why. It's a legacy script. Long story.) We're tweaking this
script to use --o_direct when tarring the file to tape and that seems to be
working fine:</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=583474619-03092004><FONT face="Courier New" size=2># tape
device is /dev/nst0</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face="Courier New" size=2>$ tar
--o_direct -cvf /dev/nst0 /ocfs/RMAN_test_file
<BR>./RMAN_test_file</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2>But, to pull that
same file back off tape and save it to the original OCFS location, it seems that
we cannot use --o_direct:</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=583474619-03092004><FONT face="Courier New" size=2># skipping
commands to reset the tape pointer to the proper location</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face="Courier New" size=2>$ tar
--o_direct -xvf /dev/nst0</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face="Courier New" size=2>tar:
/dev/nst0: Cannot open: Bad file descriptor<BR>tar: Error is not recoverable:
exiting now</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2>But, without
--o_direct, it works fine:</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2>
<DIV><SPAN class=583474619-03092004><FONT face="Courier New" size=2># skipping
commands to reset the tape pointer to the proper location</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face="Courier New">$ tar -xvf
/dev/nst0<BR>./RMAN_test_file</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004></SPAN> </DIV></FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2>We're assuming that
using the above method (--o_direct when reading from OCFS and writing to
tape, no --o_direct when reading from tape and writing to OCFS) provides us with
a proper, working file that RMAN could use for restores. </FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2><EM>Is this
assumption correct?</EM> Or, is there some issue that may bite us later? Like
something related to direct I/O, stale cache buffers, incorrect
byte-alignment, sunspots, whatever.</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2>P.S. Our RMAN
backups are happening purely on one node of the cluster, though the OCFS volume
we're writing to will be mounted by the other nodes. We may decide at some point
in the future to try backing up from multiple nodes simultaneously, but for now
we're keeping it simple. <EM>Would backing up from multiple nodes simultaneously
change the answer to the above question?</EM></FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2>For the record,
we're using the following:</FONT></SPAN></DIV>
<UL>
<LI><SPAN class=583474619-03092004><FONT face=Arial size=2>Red Hat Enterprise
Linux Advanced Server 3.0 Taroon Update 2 (kernel
2.4.21-15.ELsmp)</FONT></SPAN></LI><SPAN class=583474619-03092004><FONT
face=Arial size=2>
<LI><SPAN class=583474619-03092004><FONT face=Arial size=2>Oracle Enterprise
Edition 9.2.0.5</FONT></SPAN></LI>
<LI>ocfs-2.4.21-EL-smp-1.0.13-1</FONT></SPAN></LI>
<LI><SPAN class=583474619-03092004><FONT face=Arial
size=2>ocfs-support-1.1.2-1</FONT></SPAN></LI>
<LI><SPAN class=583474619-03092004><FONT face=Arial
size=2>ocfs-tools-1.1.2-1</FONT></SPAN></LI>
<LI><SPAN class=583474619-03092004><FONT face=Arial
size=2>coreutils-4.5.3-35</FONT></SPAN></LI>
<LI><SPAN class=583474619-03092004><FONT face=Arial
size=2>tar-1.13.25-16</FONT></SPAN></LI></UL>
<DIV><SPAN class=583474619-03092004><FONT face=Arial size=2>Thanks in
advance,</FONT></SPAN></DIV>
<DIV><SPAN class=583474619-03092004></SPAN><FONT face=Arial><FONT size=2>M<SPAN
class=583474619-03092004>att</SPAN></FONT></FONT></DIV></BODY></HTML>