Guidance on configuring LUNs

[David Foard]

Is there any documentation that provides guidance on defining and sizing LUNs? I have a multi-server BI configuration consisting of the following servers:
1. ETL
2. BI database (dimension and fact tables)
3. OLAP database (cubes)
4. SharePoint/RS server farm

I know that I need to create separate LUNs for log, tempdb and data. The question I have is do I need to create these LUNs for each server or can they be shared across all the servers?

I am thinking I need to at least create separate LUNs for logs and tempdb for each server and then create LUNs for data based on the workload, e.g. 1 LUN for ETL/staging, 1 LUN for OLAP cubes and then another for the presentation servers.

I realize there will be a fair amount of testing and validation to make sure this work for my environment, but I am just looking for a decent starting point.

[Richard Tengdin · Accepted solution]

If this is Windows you will need one set of volumes for each server (or Windows cluster), not per function. NTFS is a shared-nothing file system so Windows does not have any way to coordinate file access between two servers.

You should also have individual volumes for each server to avoid I/O contention on the volume.

There are cluster file systems for Windows available (StorNext from Quantum for one) but they aren't designed for database use.

[IBaltay]

Hi,
if its Linux or Windows the HP/Polyserve Matrix cluster files sytem could be considered to make use of the possible parallelism of the multiple hosts but the apps should support it. Polyserve also has two types of the FS: one as a classical file optimized and the db optimized for e.g. oracle direct caching... On Linux it supports also Ora RAC with Oracle shared home...

File systems

In general ora log files (redo/archive) - raid1)
datafiles (raid5)
all as separate LUNs
mirrors as separate LUNs