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			|  Using ASM without raw disks? [message #112235] | Wed, 23 March 2005 17:52  |  
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					| deesto Messages: 36
 Registered: March 2005
 Location: NY, USA
 | Member |  |  |  
	| I realize the whole point of employing ASM in an enterprise environment would be to alleviate the need for third-party LVMs and data management at the OS level. 
 Still, I wonder if there is a way around the raw disk requirement for using ASM-- not in a production environment, but for the purpose of getting aquainted with its benefits and intricacies, and running through its procedures without impacting a live enviromnent (and to save the time and expense of additional hardware installation.
 
 I have read about an "undocumented" ASM parameter called ASM_ALLOW_ONLY_RAW_DISKS, which, when set to FALSE, would allow me to do what I need to do without additional disks:
 http://www.orafaq.com/parms/parm50.htm
 http://www.dbazine.com/OLC/still.shtml
 
 Unfortunately (but not surprisingly), this hasn't worked for me thus far.  Has anyone had any luck with this parameter in a WinXP environment?
 
 Any ideas on what _might_ work toward reaching this end would be greatly appreciated.
 
 Thank you.
 John
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			| Re: Using ASM without raw disks? [message #113561 is a reply to message #112235] | Mon, 04 April 2005 11:14   |  
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					| Frank Naude Messages: 4596
 Registered: April 1998
 | Senior Member |  |  |  
	| I've managed to get it to work on a Solaris machine. Unfortunately I don't have a Windows box to test on. 
 
 $ mkdir /app/oracle/asmdisks
$ dd if=/dev/zero of=/app/oracle/asmdisks/disk1 bs=1k count=1000000
1000000+0 records in
1000000+0 records out
$ dd if=/dev/zero of=/app/oracle/asmdisks/disk2 bs=1k count=1000000
1000000+0 records in
1000000+0 records out
 
 SQL> alter system set "_ASM_ALLOW_ONLY_RAW_DISKS" = FALSE scope=spfile;
System altered.
SQL> startup force;
ASM instance started
Total System Global Area  155189248 bytes
Fixed Size                  1300760 bytes
Variable Size             153888488 bytes
Database Buffers                  0 bytes
Redo Buffers                      0 bytes
ORA-15110: no diskgroups mounted
SQL> CREATE DISKGROUP testDG normal redundancy disk
  2     '/app/oracle/asmdisks/disk1',
  3     '/app/oracle/asmdisks/disk2';
Diskgroup created.
 Best regards.
 
 Frank
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			| Re: Using ASM without raw disks? [message #115263 is a reply to message #113561] | Fri, 08 April 2005 10:56  |  
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					| deesto Messages: 36
 Registered: March 2005
 Location: NY, USA
 | Member |  |  |  
	| I can verify at least that the command to set the parameter works in Windows: 
 SQL> alter system set "_ASM_ALLOW_ONLY_RAW_DISKS" = FALSE scope=spfile;
 
 I think one thing to note would be that this parameter is valid ONLY after creating an ASM instance. If I recall, I tried setting this parameter before creating the instance, and it didn't work.
 
 I just wish I had been able to find this out a few weeks ago... would have saved me a whole bunch of headaches!
 
 Thank you Frank,
 John
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