Our new DAS unit is on the horizon and I'm looking for the best way to configure the storage.
We currently use vSphere 6.0 but will have to upgrade to 6.5 when Update 1 is released as all HDDs in the new DAS are 512e (sector size is 4096 emulated as 512) which is only supported in 6.5.
The total capacity of two Dell MD1280 (populated with 10TB HDDs) will greatly exceed 64 TB max size of Datastore, many times. Depends on the number of hard drives we decide to use/buy.
Initially I thought about creating multiple Virtual Disks in iDRAC
RAID5 -> 7 x 10TB = 60TB with 1 drive failure
Then create Datastore and Virtual Disks with vCenter and then span them with LVM on the VM (all VMs are Linux)
This is the same and only option I was given by DELL VMWare tech support.
The problem here is that if I fully populate the both units, I would lose 24 drives (240TB) for parity and still only one of them can fail per each Virtual Disk. Any other RAID level only adds to the loses.
I used RDM approach (mounting physical(VDs from iDRAC) drives on VMs) in the past while running vSphere on a Free licence to work around max 4TB Virtual Disk size. I wonder if that would work and what would be the possible downsides of this approach, if it works on this scale.
I know I might be forced to do this outside of VMWare and be able to just span all HDDS into a huge array with multiple parity disks but wanted to ask if anybody has some word of wisdom in this subject. Details of this approach should probably be discussed in a separate question, if there isn't one already.
Any advice would be greatly appreciated.