Disk Layout in HP-UX 11.31 for Oracle 10G ASM

[Chandan Laskar]

In our environment HP-Unix Server are connected with EMC CX4 storage. Fiber connectivity is there between server and storage.
We need to install Oracle 10G (10.2.0.4) with ASM.

Can any body suggest me the disk layout for this installation?

I am attaching a sample FileSystem layout for one of the Oracle server currently running in our environment.

Please revert if you need any further clarification.

[Jean-Luc Oudart]

Hi

Why do you require ASM ?
will you be using clustering (RAC)?
Is this only one instance ?

just trying to get the reason for ASM, especially if you have a single instance and no RAC.

Regards
Jean-Luc

[Chandan Laskar]

Hi,
First of all thanks for your queries.

Please find below the answer:
We are planning for ASM because of better I/O performance.

No we will not configure Cluster.

Yes this is only one instance which will use ASM.

Please revert if you need any further input/clarification.

Regards,
Chandan Laskar

[Viktor Balogh]

Hi,

here is a document on how to migrate the database to ASM:

http://sve.to/wp-content/uploads/2009/08/oracle10g_hpux_raw_to_asm.pdf

and this thread might help decide if whether ASM or LVM:

http://h30499.www3.hp.com/t5/Serviceguard/Oracle-11g-using-ASM-raw-or-slvm/m-p/4443864#M16779

Regards,
Viktor

[Chandan Laskar]

Hi Victor,

Thanks for your advice. But it is not exactly in-line with my requirement.

Please check the attachment.
Do I need to take different Physical Volume of all the mentioned space in excel file?

Can I use the same name (i.e. /redolog1, /redolog2, /redolog3,
/redolog4, /oraclebin, /oradata1, /oradata2,
/oradata3, /oradata4 & /oraarch) for ASM environment?

Please advice.

Regards,
Chandan Laskar

[Viktor Balogh]

>Do I need to take different Physical Volume of all the mentioned space in excel file?

AFAIK you should assign LUNs from your storage, and you need to create hard links to these luns with mksf for not to interfere with insf. (insf would clear the ownership from the disk device files)

>Can I use the same name (i.e. /redolog1, /redolog2, /redolog3,
/redolog4, /oraclebin, /oradata1, /oradata2,
/oradata3, /oradata4 & /oraarch) for ASM environment?

keep in mind that ASM doesn't work on the filesystem level. So you don't need mountpoints anymore. Just present LUNs which are equal in size to the existing filesystems, create hard links with mksf, and assign these to the oracle user with chown. It's as simple as that. But I suggest to find a howto on the oracle site and follow that guide.

Also keep in mind that ASM isn't able to store any kind of data: the database itself should be located on a normal filesystem, (which in turn can reside on LVM). But for this see the excellent post of VK2COT from the above linked thread.

[Viktor Balogh]

>Do I need to take different Physical Volume of all the mentioned space in excel file?

Physical Volume is a concept from LVM, which you would avoid with ASM.

[Chandan Laskar]

Hi Victor,
Many Thanks for your explanation. It really shows your detailed knowledge on ASM.

Only I need your further advice to understand some more areas as mentioned below:

-- You have mentioned that "Just present LUNs which are equal in size to the existing filesystems, create hard links with mksf, and assign these to the oracle user with chown".

-Q: How these LUNs will be identified? can it visible through BDF command? Has Operating System assigned any default name for those LUNs? And is it mksf command or mkfs command?

-- You have mentioned that "Also keep in mind that ASM isn't able to store any kind of data: the database itself should be located on a normal filesystem, (which in turn can reside on LVM)".

-Q: Can it possible to store Oracle Data files (.dbf) in LUNs which is managed by ASM?

Regards,
Chandan Laskar

[Viktor Balogh]

-Q: How these LUNs will be identified? can it visible through BDF command? Has Operating System assigned any default name for those LUNs? And is it mksf command or mkfs command?

The LUNs will be visible in the ioscan output, not in bdf output. In bdf you can see the filesystems mounted, and ASM is just one below the filesystem layer. The command is mksf, (memorize it like "MaKe Special File).

-Q: Can it possible to store Oracle Data files (.dbf) in LUNs which is managed by ASM?

AFAIK there is no need to have a datafile with ASM, the data will be stored directly as to a raw device

[Chandan Laskar]

Hi Victor,

Many Thanks. Your advices helped me a lot to understand the Oracle ASM preparation activity.

I am from Kolkata, India . Now it is 08:16 P.M... I need to pack up. Tomorrow, if needed, I may seek your further help.

Hope you will give me similar high quality technical advice.

Thanks again.

Regards,
Chandan Laskar