Windows Storage Server 2016 - Hyper-V and LUNS

[ghockin]

Morning all.

 

We have just purchased our new 30TB San. Our plan is to connect our bare metal Hyper-V servers to the SAN and then setup Hyper-V high availability, which works really well.

 

I have all the technical bits sorted out and know how to do the setup but I'm confused by one thing, LUNS?

 

I've read you shouldn't have a LUN that is bigger than 2TB?

 

Also what constitutes a LUN? Is it a disk partition where you store the iSCSI disk, or the iSCSI Disk itself?

 

Id be curious to see how other schools setup the LUNS on their SAN, do you have one big area for storage of VMs, or lots of smaller storage areas.

 

Cheers

 

Gary

[Davit2005]

A LUN is a slice of some storage that you give to a host or hosts. Either connected by Fibre Channel or iSCSI

 

You should be able to tie the access down to specific hosts, I'd suggest that when you setup the LUNs you do some form of Masking on the SAN. It is not difficult to do but INMO well worth it. Basicaly you give access to only hosts that should have access to the LUN.

 

For instance if you were to mount a VMFS formatted LUN to a windows host with write permission you would prob corrupt it.

 

Here is one such article on Google https://kb.netgear.com/23292/What-are-basic-LUN-concepts-I-need-to-know-before-using-my-ReadyNAS-OS-6-storage-system but you may beable to get some info from the manaufacturers of the SAN disk unit.

Edited January 29, 2021 by Davit2005

[Norphy]

LUN stands for Logical Unit Number. It's essentially the storage volume on the device itself, which your server attaches to via iSCSI, FC, FCoE or SAS.

 

It's up to you how you set up your volumes. There is no reason to restrict yourself to 2TB LUNs; Windows will quite happily address multi terabyte volumes, as long as the volume is a GPT volume. There are advantages to either approach but on my Compellent SANs I have multiple smaller volumes on which I store either one VM or a group of related VMs.