we are about to setup a new VDI infrastructure on a v7000 storage.
storage capacity is abbout 40TB with 20 SSD disks for flash.
which is the best way to setup the VDIs? what raid groups? how many VDIs per LUN etc etc
Message was edited by: Brian Atkinson to remove the ALLCAPS from the subject line
Well this would depend heavily on how many VDI VM's you plan to deploy and what your IOPS requirements are. However seeing as you have 40TB with 20 SSD disks I don't think IOPS will really be a problem. Also since your using all SSD your raid level will matter a litte less then say with 10K or 15K SAS drives.
RAID 10 will always get you the best read/write performance, however you loose the most amount of space with it.
RAID 5 or 6 would probably suit you fine and get you some more usable space out of your 40TB/20SSD disks.
Typically the hardest hit to the SAN in a VDI enviroment is in the morning or when a large amount of shifts start. In most cases you will see a few hundred VM's firing up in the mornings but then it levels out throughout the day so your configuration needs to be able to handle that spike to ensure a smooth transition for your users.
How are you connecting your V7000 iSCSI?
Well seeing as you have all SSD connected with FC I would go with RAID6 and split out the VM's equally. This will give you more usable disk space allow for 2 disk failures in your raid set. So if you have 100 VM's i would create 4 Datastores and split 25 VM's out per datastore, you probably could get away with one or two LARGE datastores but this will give you more finite controll over your IO at a LUN level.
Another thing you could do to get a better idea of IOPS requirements of the systems you plan on replacing with VDI is install Microsoft MAP tool and let it run performance metrics on those systems for a week or two. This is a free tool from Microsoft to help with sizing virtual enviroements. It will spit out some really nice spreadsheets with how much CPU, Memory, Disk IOPS, Disk space, and network utalization each system is using. It will even break it down into the Low, High, Average, and 95th percentile.
Hopefully more of the VDI people could chim in and give you some other ideas as well.
Hope this has helped,
My recommendation is to create a hybrid pool in your V7000 and place the HDD and SSD on that pool, then the Easy Tier will move the hot extents from SSD 🙂
The V7000 configuration is a important step, try balance the disks between the V7000 chains to get the best performance.