Best Practice for configuring a Storage Device - Dell MD3000I

[jonnysideways]

Good morning all.

I know this question gets asked in many ways across the communities, and it may seem like a daft question, but all the same here goes.

If I have the following scenario, what is the best way to configure my VMware Storage, from the Arrya, Virtual Disk on the Array and down to Data Store and VM disk Level.

Dell MD3000i With 4TB.

I Wanted to Configure Raid 10 for my chosen protection, do I create 1 x 2TB Raid 10 Array with all my disks, then assign the whole chunk to a vm data store, or split the array into 2 x 1TB virtual array disks, then assign them to 2 vm data stores. (The deafult when chosing auto configuration is the later see attached screen shot)

Or have I missed the point, as I've seen some where about it being good practice to assign the virtual drives on the array as the same size as the actual vm that is created, but that may just be when creating pass through mappings.

In a previous implementation I had 2TB on a Fibre San, split it into two 1TB logical drives, created to data stores and configured multi pathing to give best performance, then just created vms across the two data stores based on space and load.

Thanks in advance

[mjpagan]

I would recommend multiple datastores, that way each path will be used. One for each LUN. I am guessing though based on the amount of disk space you have, that either option would be just fine because in the grand scheme of things there won't be that much I/O to really matter.

Mike P

MCSE, VCP3/4

[jonnysideways]

So in my case if I create 2 virtual disks on my San, then 2 datastores. Or shoul I create as many virtual disks as I have paths I.e four as that how many iscsi ports the md3000 has?

[mjpagan]

I would create two LUNs on the SAN and two datastores out of those LUNs in VMware.

The MD3000i has 2 ports per controller, equaling 4 ports total. Typically you use port0 in each controller for storage network A and port1 for storage network B for mulipathing and redundancy reasons.

Check out this configuration guide for more information: http://www.delltechcenter.com/page/VMwareESX4.0andPowerVault+MD3000i

Mike P

MCSE, VCP3/4

[jonnysideways]

Makes sense cheers. I was going to read guide this weekend but you've cut through the mist cheers.

[jonnysideways]

Makes sense cheers. I was going to read guide this weekend but you've cat through the mist cheers.

[Phokay]

Rule of thumbs:

1. One LUN (volume) per data store (never ever configure just one LUN for the whole SAN)

2. Target your data store size for 8-10 VMs max (to reduce scsi reservations on the LUN)

3. Assign LUNs to different controller/path manually on the storage (as well as in VI client if necessary) to achieve load balancing across SPs.

4. Listen to experts.

[jonnysideways]

Cheers

One final daft question, when I add my ISCSI Device using the dynamic discovery Send Targets page on the software initiator (vmhba37) properties tab it shows on the Static discovery that there are 8 discovered paths.

Do I need to add an entry on the dynamic discovery tab ofr each ip address of my ISCSI ports on my iscsi device i.e 192.168.50.10/20 & 192.168.51.10/20 or can I jst leave the one entry? which is the fqdn currently.

cheers

John

[Josh26]

Rule of thumbs:

1. One LUN (volume) per data store (never ever configure just one LUN for the whole SAN)

I'm trying to follow this blanket statement.

In a small SAN environment where the whole SAN is within the 2TB limit for a VMWare LUN, for what reason would I not want to configure just one LUN?

[mjpagan]

That might be the one of the only deviations from the "rule" that I can think of. Sometime's it's nice to have two LUNs during the eval period of the licensing so you can Storage vMotion your VMs to thin them out but if you have a SAN/NAS that small I'm fairly certain that they won't be running Enterprise licensing after the eval is over.

Mike P

MCSE, VCP3/4