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Best Practice for Partitioning SAN?

We have an Equal Logic PS5000XV 300Gbx16 coming to us to act as the datastore for our new completly virtual environment. Exciting! We'll be running RAID50.

We're looking for suggestions on how to partition the SAN?  Is there a best practice?
We're going to have 5 VM's running in this environment.  Average I/O is about 1100.

All machines are running w2k3 Enterprise:
All sizes are capacities USED on the current machines.

Exchange and File Server  = 95Gb
IIS Server & SQL Server = 396Gb
Email Hosting and DNS Server =  50Gb
Development Server = 18Gb
VirtualCenter = 10Gb

We'll be separating the above SQL server to be on it's own sometime next year.

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Dell/Equallogic should have documentation regarding provisioning LUNs for your VM environment. Each vendor has different requirements for provisioning your VMs. It's not just LUN size, but performance on those LUNs (are they running RAID10, RAID5, etc?).

I would contact your Dell-Equallogic support and have them send you documentation with their best practices for provisioning LUNs for your VMs as well as documentation for each application you listed here (if they have it).

Typically you would set up a LUN to be a certain size (Say 500GB) and run x VMs on it. Certain applications may require that you add LUNs to be used as RDMs attached to the VMs. You can look to VMware for documentation on that if D-E don't have it.

For example, a SQL server may be assigned to LUN1 (500GB RAID5) and has LUN2 (RAID10 50GB) attached as an RDM for Transaction logs.

Follow the disk requirements (RAID level) for your application, and that will determine what types of LUNs to create and assign your VMs to.

Also, have a LUN naming convention that matches in your SAN console and your VirtualCenter console. For example,

Basic LUN Mapping
LUN0 - Boot LUN for ESX (Optional - Reserve for later)
LUN1 - Templates/ISO/General Storage
LUN2 - OS/DATA (Server group1 - High performance - 4 VM's - C:/D:/E: Drives)
LUN3 - Pagefile (Paired with LUN2) for VM pagefiles (P:\ Drives)
LUN4 - LUN9 - Reserved LUNs for virtual machine RDM's for machines in this group

LUN10 - OS/DATA (Server group2 - Low performance - 16 VM's - C:/D:/E: Drives)
LUN11 - Pagefile (Paired with LUN10) for VM pagefiles (P:\ Drives)
LUN12 - LUN19 - Reserved LUNs for virtual machine RDM's for machines in this group

LUN20 - OS/DATA (Server group 3 - Certain application - 6 VM's - C:/D:/E: Drives)
LUN21 - Pagefile (Paired with LUN20) for VM pagefiles (P:\ Drives)
LUN22 - LUN29 - Reserved LUNs for virtual machine RDM's for machines in this group

Advanced LUN Mapping
LUN0 - Boot LUN for ESX (Optional - Reserve for Later)
LUN1 - Templates/ISO/General Storage
LUN2 - OS (Server group1 - High performance - 3 VM's - C: Drives)
LUN3 - PROGRAMS (Server group1 - High performance - D: Drives)
LUN3 - DATA (Server group1 - High performance - E: Drives)
LUN4 - Pagefiles (Paired with LUN2 - P:\ Drives)
LUN5 - LUN9 - RDM for a VM to use (Can be added later)
LUN10 - OS (Server group2 - Certain Application - 4 VM's - C: Drives)
LUN11 - Pagefiles (Paired with LUN10 - P:\ Drives)
LUN12 - RDM for AppVM1 (D:)
LUN13 - RDM for AppVM2 (D:)
LUN14 - RDM for AppVM3 (D:)
LUN15 - RDM for AppVM4 (D:)
LUN20 - OS (Server group3 - Low performance - 16 VM's - C:/D:/E: Drives)
LUN21 - Pagefiles (Paired with LUN20 - P: Drive)
Since the "Basic LUN Mapping Layout" is sufficient for most environments, we recommend you follow it unless your environment has special needs like those shown in the "Advanced LUN Mapping Layout".
The LUN Mapping examples were derived from another SAN vendor's Best Practices (Compellent), which is why I urge you to contact Dell-Equallogic and obtain a similar documentation from them.  

You should be able to either initiate a chat or just call them and request the documentation be sent. They may even provide you with a portal that you can go to and download the documents yourself.  

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