Red Hat

I want to make sure I'm understanding the configuration advice I've been given. Create one large LUN. Say 1 tb, for example, on the SAN side. Map that lun to the VMhost. Allocate say 600 gb to my oracle db server. The linux server should now see a /dev/sda at 600 gb?
Take that /dev/sda and partition it out into separate drives /dev/sda1 /dev/sda2.... Once that is complete I create separate volume groups and assign as many of the disks as needed per volume group?

Hi dkmartin,

I'll reiterate, there is a dependency on the backend configuration.

If you have a requirement to slice and dice a 1Tb LUN, you'll end up (from your comments) /dev/sda1, /dev/sda2, /dev/sda3 etc....... These would then be used for the "rootvg", the "appvg" the "dbvg" or any other way that you decide to apportion the disk.

If you decide to go for individual LUN's then you would have effectively a "ROOT_LUN", an "APP_LUN" and a number of "ORACLE_LUNS" for things like redo, archive, table space and all the other bits of an Oracle Instance - basically whatever your standard build is.

Without knowing what the backend storage is and how it is configured, how the storage is managed and how it is tiered are the arrays intelligent along with a miriad of other requirements it isn't possible to be any clearer with the information.

At the back end this could be all on one physical disk (You don't want that) or it could be spread over many physical disks.

For simplicity of management a single LUN is good, if the I/O on the VM will allow you to do that without impacting performance.

As to this being "configuration advice" it is not, there is no way that any advice could be given based on what you have told me - the sum total of the knowledge inparted by yourself is that "It's currently AIX and it's moving to Linux on VMware - the LUN mentioned is 1Tb and you use Oracle".

Oh! and it won't be using ASM.

Regards

Gull04

On VMWARE i would recommend using RDM, multiples of, in SAN environments.

Inside the guest, use ASM and minimize filesystem caching via kernel parameters, since you will not need it.
If filesystems are used, go XFS and limit the filesystem caching considering the size of SGA / PGA from Oracle side.
Check out the tuning docs regarding from Oracle side.

In either case, using ASM or XFS with volume manager, be sure to separate REDO, DATA and archive logs do use different RDMs.

On storage side, set new page assignment on REDO LUN to hit the fastest you have.
DATA then comes second disk performance wise, while archive logs can be slowest rust.

Use storage to provide snapshots, cloning and stuff.
One monster lun then datastore then guest database sure sounds like a nightmare from my perspective.

Hope that helps
Regards
Peasant.