UNSOLVED

DWormsbecher

updated

9 years ago

0

3328

November 15th, 2017 06:00

Unity VMFS Datastore Simple but Fast

Hi Folks,

what's your best practice?

I have an Unity 400, mixed Pool (some Flash, some 10k SAS drives).

I would like to create one LUN and present this to 4-5 Vmware Host.

Unity is Actice-Active Controller by Design right? But as LUNs are still ALUA, it would be a good Idea to create a LUN for SPA and SPB, right?

How is about two Expand the VMFS Datastore created on LUN0(SPA) by the space from LUN1(SPB), good Idea or not?

Thanks and Regards

Didi

  • SteveK821

    2 Intern

    153 Posts

    2541

    0

    Posted November 17th, 2017 01:00

    It depends what else is on the array. Generally you should try and balance the load across both SPs. So create at least 2 Datastores, one owned by SP-A, one by SP-B. A LUN or Datastore is online to one SP, VMware will only send I/O to the SP owning the datastore. You will see half the paths as "Active (I/O)" and the other half as just "Active". The Multipathing should be using VMTP_ALUA_CX and Round Robin.

    I am guessing you are using Fibrechannel so make sure all ESX hosts are zoned to ports on both SPs.

    I don't understand what you mean with your last question.

    Have you connected the Unity to your vCenter server? (In Unisphere: Access -> VMware) If so, then you can create a new VMFS datastore in Unisphere (Storage -> VMware), then decide which Hosts can access it. The Unisphere wizard will then contact vCenter and tell it to rescan for new datastores, setting up the new Datastore automatically.

    Regards,

    Stephen

  • 2541

    0

    Posted November 17th, 2017 02:00

    I mean, you can add two Datastores for sure.

    But what if I add LUN0 as Datastore and expand this one by extend from LUN1.

  • SteveK821

    2 Intern

    153 Posts

    2541

    1

    Posted November 17th, 2017 04:00

    You could do that. But why would you need to use extents? VMware doesn't stripe data across extents.

    Datastores can be expanded by increasing the size of the LUN/Datastore on the Unity.

    I had never heard of this before (extents in VMware), but here's an interesting blog post:

    https://blogs.vmware.com/vsphere/2012/02/vmfs-extents-are-they-bad-or-simply-misunderstood.html

    I don't think you can use the integration between Unisphere and vCenter to configure this. You would have use the LUN/Block assignement method (the old-fashioned way) and manually set up the Datastore in VMware.