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Transfer of 30GB by DDS2

 
Ian McClement_1
Occasional Advisor

Transfer of 30GB by DDS2

Hi
I need to transfer Approx 30GB worth of Oracle Data (unexported) to nw server via DDS2 Tape (Max 12GB).
We only have approx 9GB of space at OS level for exporting, so is the best way to export direct to tape? and via a piped file to reduce the potential points of failure.
Exporting straight to compressed file, then copying files to tape is an option, but do not know total size of exported DB.

Any advice/help more than appreciated
Cheers
Ian
8 REPLIES 8
Stefan Farrelly
Honored Contributor

Re: Transfer of 30GB by DDS2


Getting 30Gb onto DDS2 tapes isnt a problem, your database should compress well and if you use fbackup or the gnu version of tar it will span multiple tapes.

I dont know if oracle export can handle writing to multiple tapes, I think not (ie. asking for a new tape for export to continue).

I think you need to dump to disk somewhere first (compressed) then write to tape using fbackup.
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twang
Honored Contributor

Re: Transfer of 30GB by DDS2

If you can shutdown the oracle instance, I would suggest you to copy datafile one by one via network or DDS2 tape.
If you want to export the database, the following way can redirect the dmp file to be compressed:
# /usr/sbin/mknod exp_pipe p
# gzip < exp_pipe > FULLDMP.dmp.gz &
# exp sys/ file=exp_pipe full=y buffer=4000000 statistics=NONE log=EXP.log
Carlos Fernandez Riera
Honored Contributor

Re: Transfer of 30GB by DDS2

If you want to do a copu of all datafiles just create a script grouping datafiles up to 12GB


If you want to do an export i would try it directly:

exp will not export data of indexes, temporal and rollback datafiles, just the data. And thos type of files ( .dmp) can compress more that 2:1 ( i think more than 3:1), so one tape should be enought.

In addition you can use the size clausule for teh exp command, exp file=/dev/rmt/0m log=.... size=
. I cant find size= with exp help=y but i think it exists.
unsupported
Paula J Frazer-Campbell
Honored Contributor

Re: Transfer of 30GB by DDS2

Ian

Can you not ftp it to the new server?

Paula
If you can spell SysAdmin then you is one - anon
Yogeeraj_1
Honored Contributor

Re: Transfer of 30GB by DDS2

hi,

You would export to a device that does not support seeking such as a tape (not recommended, really slow) or a pipe.


Using compression AND split to make the export be in many managable sized file (500meg is my chosen size) will solve the problem.

Basically, you would create a pipe in the OS via:

$ mknod somefilename p

and then export to that pipe. you would set up another process in the background that 'eats' the contents of this pipe and puts it somewhere. I use split, you could use 'cat' to just put it into another file (if cat supports files >2 gig -- thats the problem here, most utilities do not, you need to use a special file io api to 2 gig file support).

Here is a script you can use as a template.

------------------------------
#!/bin/csh -vx

setenv UID /
setenv FN exp.`date +%j_%Y`.dmp
setenv PIPE /tmp/exp_tmp_ora8i.dmp

setenv MAXSIZE 500m
setenv EXPORT_WHAT "full=y COMPRESS=n"

echo $FN

cd /nfs/slx2/expbkup_ora8i
ls -l

rm expbkup.log export.test exp.*.dmp* $PIPE
mknod $PIPE p

date > expbkup.log
( gzip < $PIPE ) | split -b $MAXSIZE - $FN. &

# uncomment this to just SPLIT the file, not compress and split
#split -b $MAXSIZE $PIPE $FN. &

exp userid=$UID buffer=20000000 file=$PIPE $EXPORT_WHAT >>& expbkup.log
date >> expbkup.log


date > export.test
cat `echo $FN.* | sort` | gunzip > $PIPE &

# uncomment this to just SPLIT the file, not compress and split
#cat `echo $FN.* | sort` > $PIPE &

imp userid=sys/change_on_install file=$PIPE show=y full=y >>& export.test
date >> export.test

tail expbkup.log
tail export.test

ls -l
rm -f $PIPE
--------------------------------------------------

This also always does an 'integrity' check of the export right after it is done with an import show=y, that shows how to use these split files with import.



hope this helps!

Regards
Yogeeraj
No person was ever honoured for what he received. Honour has been the reward for what he gave (clavin coolidge)
Paula J Frazer-Campbell
Honored Contributor

Re: Transfer of 30GB by DDS2

Ian

Can you not ftp it to the new server?

Paula
If you can spell SysAdmin then you is one - anon
Yogeeraj_1
Honored Contributor

Re: Transfer of 30GB by DDS2

hi again,
attached the script!

regards
Yogeeraj
No person was ever honoured for what he received. Honour has been the reward for what he gave (clavin coolidge)
Michael Steele_2
Honored Contributor

Re: Transfer of 30GB by DDS2

Can you post the product number please?

I believe a DSS2 is limited to 120 meter tapes while 125 meter tapes only apply to DSS3 and DSS4. Here are the native / compressed sizes for all DAT's:

DSS4 = 20 gb / 40 gb

DSS3 = 12 gb / 18 gb (* some advertise 24 gb but I believe its 1.5 compression. *)

DSS2 = 4 gb and 8 gb.

DSS1 = 2 gb and 4 gb.

NOTE: Never use software compression with firmware compression.
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