SAN LUN Layout

[BypipLtd]

I suspect this question has been asked many times, but heres my specific scenario.

We have already purchased a 10Gbs SAN with pure SSD storage, no spindles. We are rolling out Horizon 8.7, and as part of the design work Im now looking at the SAN/LUN config. Can I first say that the purchase of the SAN was done as the supplier was promoting it before year end, as I personally dont see the benefit of all SSD - but I am happy to be wrong. So, back to the query. We have 7 drives included in the SAN (and one will be used as a Hot Spare), giving us 6 usable drives. We will want at least two pools available, and we need to accommodate up to 400 users maximum. Im trying to come up with a design to best utilise the available capacity. Each pool will have its own golden image. So, are we looking at single/multiple RAID arrays, and of these whats the best use when it comes to splitting these into LUNS/Datastores for the Replica and Linked Clones. Im trying to avoid wasting disk space, but as these are SSD on 10GBs then Im also wondering if the replica and linked clones can/should be on a single LUN, but I understand this reduces the amount of iscsi paths to the SAN... Im sure a number of you will have been faced with this same situation, and wanted to know what was your choice and for what reasons?

Thanks for any help

Phil

[BenFB]

All-flash arrays (SSD or NVME) are almost always a necessity for virtual desktops. Typically you want to work with your SAN vendor to architect the layout. I'm not seeing any mention of thin provisioning, global deduplication, etc.. Is this a SoHo NAS? Regardless, see the VMware Horizon 7 sizing limits and recommendations (2150348)​. The recommendation is no more than 500 VMs per datastore but you need to ensure that the array can deliver the requires IOPS.

Are you set on doing linked clones? Instant clones or full clones/standalone vCenter VMs behave differently.

[BypipLtd]

Hi, thank you. No, this is an Enterprise SAN from Fujitsu. I have mentioned that I need to plan the placement of the Replica and Linked Clones. I will take a look at the link now. Thank you. Phil

[BenFB]

I would recommend working with Fujitsu or a VAR to architect this. With only 7 drives it's going to be important to size it correctly. There are a lot of variables that will depend on the capabilities of the array.

[mchadwick19 · Accepted solution]

If this is an all-flash array I would recommend 1 LUN dedicated to your master/gold images. Then I would recommend multiple equal sized LUNs and store your replica's with your linked-clones. When the clones are provisioned each datastore selected would get a replica for that pool. It spreads the load quite a bit better than a single replica LUN and multiple clone LUNs. The 1 replica LUN (I believe) was geared towards a hybrid/tiered array where you would pin your replica LUN to your fastest storage and then your clones would sit in tier 2/3 storage that way reads would come from fast disks and writes would go to slow(er) disks. That's not the case with all-flash.

[BypipLtd]

Thank you mchadwick19 for this clarification. It does marry up with my initial thoughts, but did want to get differing views on it too. Thanks all for your help.