export oracle database from the snapshot

[EAB]

Hi,
we have oracle RAC installed at 2 machine RX8620 , we are going to use snapshot methedolgy for EVA5000,
as we spend around 4 hours daily durin End of day for the export database , we need to eliminate this time , so how we can use this snapshot to export this cluster database which is using raw device , and how we can access to run the oracle export utility from the same machine

[Steven E. Protter]

Shalom,

Methodology:

Shut down database.
Make snap shot. (take action to make sure its clean)
bring up database.

Should not take more than 10 minutes.

You may not be able to run the export utility from the same machine, because of instance name conflict.

But you have a cold backup now and can run export on it from another machine.

SEP

[EAB]

Hi,
i didn't want to shutdown the database , i think it is applicable to take snapshot for the database at certain time although it's open as it is not snapclone,
so i need to how to defined this snapshot at the HP-UX machine and how to get the database ready for the export

[Orhan Biyiklioglu]

You do not need to shutdown the database.
Just switch your tablespaces to backup mode before taking the snapshot and switch back after the snapshot.

You should also backup the control file and init.ora files.

You will need the achieved log files to open the snapshot db on the second node. So you should switch logfile and copy your log files to the second node.

See

http://www.informit.com/articles/article.asp?p=30348&rl=1

hth

[EAB]

Hi,
thank u for ur response , this is means that i have to fire command for converting the database in backup mode , then take the snapshot image ,
after that what is the steps to get the image of this database accessible from other server to get the export dump file
and how long will this snapshot take time for 300GB to finish and return the production database to the norml mode

Thanks

[patrik rybar_1]

if you do not want shutdown db , you can look at backup through this way :
suspend database i/o activity via
ALTER SYSTEM SUSPEND;

Split your mirrors at the O/S or hardware level
or make snapshots

than

ALTER SYSTEM RESUME;

maybe this will be usable for you
bye

[Yogeeraj_1]

hi,

You can also modify your scripts such that you can issue several EXP in parallel.

You may export schema individually or even tables.

For huge tables, you can as well export only part of the data that may have changed only... using QUERY clause.

hope this helps too!

kind regards
yogeeraj

[Volker Borowski]

Hi,

you can use expdp (data pump) with 10g to do parallel export of the same objects to speed up the process (Test carefully, we had reproducable problems when doing export with 12 processes -> Import succeded afterwards, but had blockcorruptions in one segment while export with 8 an 16 Processes did OK).

If you do the snapshot with the DB in Backup mode, there will be need to recover the snapshot with redologs to get a consistent DB, before you can open it. I think this is not possible at all, because usually the snapshot is not modifiable ?!?!

If you can do the split OFFLINE, there might be the option to open the DB on the snapshot filesystems readonly, but also not sure about this, esp. if you have an instance with the same SID on the same box still running.

I think you will need to restore the DB elsewhere, to open it an do an export.
How big is this DB ?

Volker