Using ASM without raw disks?

Question

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

Answer 1

Hi John,
I was able to get ASM working without raw disks on Windows 2000 as follows:
create init+ASM.ora for example:
*.background_dump_dest='F:\oracle\product\10.1.0\admin\+ASM\bdump'
*.core_dump_dest='F:\oracle\product\10.1.0\admin\+ASM\cdump'
instance_type=asm
*.large_pool_size=12M
*.remote_login_passwordfile='SHARED'
*.user_dump_dest='F:\oracle\product\10.1.0\admin\+ASM\udump'
*._ASM_ALLOW_ONLY_RAW_DISKS=false
*.asm_diskstring='f:\asm\*'
The setting of asm_diskstring is very important, this should be set to the directory where you are going to create the "ASM files" that will pretend to be disks.
The asmtool which is on the Oracle 10g CRS CD, can be used to create empty files, for example:
ASMTOOL -create \\.\F:\ASM\ASMDISK1.ASM 100
ASMTOOL -create \\.\F:\ASM\ASMDISK2.ASM 100
ASMTOOL -create \\.\F:\ASM\ASMDISK3.ASM 100
This will create 3 100Mb files in f:\asm\ which with should be picked up in v$asm_disk once you asm instance is restarted.
obviously you will need to change the drive letter above, as required.
Also looks like you need the OracleCSService running, which I think can be started using ocssd.
cheers,
John