HPE Storage Users Group

We have to migrate from our current SAN with 2x45TB Datastores to a new HP 3PAR with raw ~130TB capacity.

Problem 1: This 3PAR can have a maximum of 16TB LUNs
Problem 2: We have one server with a 25TB disks
Problem 3: It seems, that VMWare can only use 2TB LUNs to extend VMware KB: Creating and managing extents on ESX/ESXi

Now I am confused what to do.
Make 32 TB LUNs and extend to to one 64TB Datastore (and do this 2 times since with have ~130TB raw capacity)?
Make on 16TB LUN and extend it with 24 2 TB LUNS?
Any other way on VMWARE side? Maybe someone here had the same problem?

What I certainly not want: extend/stripe disks in the Windows guests (so I could make 16TB LUNs with 2 big virtual disks and extend them). No way.
I also am no fan of many 16TB datastores and have to be aware of where to put a VM. Especially since the 3PAR stripes all data over all disks anyway, the LUNs are only virtual. So no performance or security gain here. It would also make the backup with veeam much more complicated.

PS: We have to do this next week...we cannot wait for VVOLs in vsphere 6.

_________________
3Par 7200 with 3 Tiers since March 2015

I guess a few questions, why only 2 45TB datastores? Is this for 2 large VMs or a collection of VMS. The easiest thing to do would be to break up the datastores. Are you coming form a NFS based datastore because if block based I am not a big fan of large block based datastores. I usually limit my datastores to 15 or so VMs each. If you have a VMs that can fit inside 16TB then make smaller datastores and storage vmotion the VMs. We have been complaining to 3par for almost 3 years that the 16TB limit is a problem especially since their OS has been 64 bit based for some time. We have asked for at least 64TB LUNs. It sounds like you have a large Windows VM?

We have a few large Windows VMs that need 30-40TB and we use pRDMs and create a Dynamic disk inside Windows. Thus each disk of the dynamic disk a a 3par LUN. It is less than ideal, but works fine. You can also use vRDMs to gain the benefits of vmdks, but either will work.

We have one big VM with one 25TB disk.
And 63 smaller ones, ranging from 80GB to 2TB.
All are thin provisioned.

Since a crash and restore time are no issue I do not see any benefits in small datastores. We will use AO on the 3par over all 3 Tiers, so everything will get balanced regardless where it resides. It just makes so much more admin work with small datastores (we have no enterprise version).

_________________
3Par 7200 with 3 Tiers since March 2015

There is not only the Problem if this big volume becommes corrupt.

If you implement in Future somthing like Veem with integrated 3PAR Backup or the new StoreOnce Recovery Manager Central, the Snapshot on the 3PAR for Backing up one VM is done on this realy big volume that includes many other VMs.
Look at ESX v6 and vVols you will see a complete different way using Datastores in future.
The Industry Trend going to have every VM there own LUN (or LUNs) in Future.

By the Way, if you sometime in Future want to use QoS on 3PAR it is better to have smaler Volumes.
And if you want to montior and Track 3PAR Performance more Volumes give you a better oversight (who is growing most, who is pulling the most Performance, ...).
And, so on...

Since the answers here are the same as in the vmware forum we will stick with 16TB volumes now, each datastore with one volume. I am looking to vvols too, but I guess this will not be in production before end if 2015

_________________
3Par 7200 with 3 Tiers since March 2015