Clone standby database without rman

[LKBrwn_DBA]

Hi guys!

I need to clone a standby database without using rman (have no disk space).

Here is the setup:
OS: HPUX
Oracle9i Enterprise Edition Release 9.2.0.6.0

Server S has standby db
Server C has mounted /oradata disk from standby

What I intend to do (if it's possible) is kinda similar to "cloning" a database from an OS hot backup:

1) QUIESCE the standby (can it be done?)
2) Copy db files from /oradata/standby to /oradata/clone
3) UNQUIESCE the standby
4) Re-create clone control file + open reset logs


Q1: Can I stop managed recovery and quiesce the standby? .. And then unquiesce and restart managed recovery?

Q2: Will copying the files be enough to clone db or do I need something else like redo/archive logs?
It's been a very looooooong time since I cloned a db from hot/cold backup.

[hrishy]

Hi

You need to just copy the datafile from the standby database to the server where you want the clone to be.

Just use the rman copy command to do this its very simple something like

RMAN> run{
backup as copy datafile 1 format 'D:\ORADATA\CLONEDB\SYSTEM01.DBF';
.....
}

take a backup of the controlfile to trace edit and to change the paths and then use it to recreate the controlfile on the clone database.

make sure you edit the first few lines to

create controlfile set database 'dbname' resetlogs

once the controlfile is created and the database mounted

recover datbase using backupcontrolfile until cancel

apply archivelogs if any to make it consistent and then open the database with alter database open resetlogs

hope you get the idea

regards
Hrishy

[LKBrwn_DBA]

Thanks hrishy,

That is exactly what I thought, unfortunately for that to work I would need space on the standby server which then I could mount unto the clone server.

That is why I thought of "quiesce" to avoid shutting down the standby during the copy and just mounting the disks unto the clone server.

Also I tried the "quiesce", but first got:

SQL> ALTER SYSTEM QUIESCE RESTRICTED
*
ERROR at line 1:
ORA-25500: database is not open

And then:

SQL> ALTER DATABASE OPEN READ ONLY
*
ERROR at line 1:
ORA-01092: ORACLE instance terminated. Disconnection forced

This is caused because I need to activate the "Oracle Resource Manager" on both the Primary and Standby (which requires shutdown/startup).

Your idea is very good, I will research how to configure the rman channels to write to remote location (vg: cloneserver:/oradata)

Any other ideas are welcome...

[hrishy]

Hi

There are no other ideas you need to NFS mount the clone server and copy the datafiles.

If thats not possible then you need to copy over the files to temp location on the standby server on a file by file basis and scp teh files over to the clone server .

Only in 11g you can clone from a live database and in all other versions you need to use the copy of the backup to clone and you need space for that.

regards
Hrishy

[LKBrwn_DBA]

If I just stop the managed recovery and copy the files, would this be equivalent to hot backup?

[hrishy]

Hi

Yes but you need to apply the archivelogs to make the datafiles consistent.

But why would you go that route ? and disturb scheme of things RMAN copy command is simple and non-intrusive and most important standby database dont ahev to play catch up with primary

regards
Hrishy

[LKBrwn_DBA]

Hi

Yes but you need to apply the archivelogs to make the datafiles consistent.

But why would you go that route ? and disturb scheme of things RMAN copy command is simple and non-intrusive and most important standby database dont ahev to play catch up with primary

regards
Hrishy

I know, every backup/clone/etc.. here I do with RMAN.

Unfortunately on this particular server we have no space for an rman backup (1.2T) therefore I have mounted the data files (mp) unto the target server where I can copy to other locations, create the controlfile and start the clone (like the old, olD, oLD, OLD procedure to clone databases)...


Thanks for your help!
.

[LKBrwn_DBA]

And the solution is:

1) Stop managed recovery on the standby:
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;

2) Copy the files from standby mp to clone mp.

3) Re-start managed recovery on the standby:
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE
DISCONNECT FROM SESSION;

4) Re-create the controlfile on the clone:
STARTUP NOMOUNT
CREATE CONTROLFILE SET DATABASE "CLONEDB" RESETLOGS FORCE LOGGING NOARCHIVELOG
-- Etc --

5) Open clone database with resetlogs

And ALL is OK!
.

[hrishy]

Hi

Congrajulations Dont just sit there its time you open a blog and blog about this :-) and tell the whole world ;-)

regards
Hrishy

[PAVB]

Nicely done LKBrwn_DBA, congrats!