Floating ISCI targets

Jon Marshall 81 Reputation points
2020-09-16T14:48:42.353+00:00

Scenario is FCM (Hyper-V) with 3 hypervisors, 2 storage head units and 1 backend MD3220 powervault. We are not connecting the
storage directly to the hypervisors as we are planning on more hypervisors hence the head units for future growth. The hypervisors and the head units are connected via a 10Gbps network.

In the past I have setup FCM with just a NAS/SAN type setup where the NAS/SAN shared out 2 ISCSI targets to the same volume and then I used MPIO on the hypervisor and this all worked fine.

With the above scenario both head units can see the same volume on the MD3220. Ideally what I would like is an active/standnby
setup where the active head unit shares out 2 ISCSI targets and each hypervisor uses MPIO to access the storage. If the active
head unit fails then the standby unit can take over the targets without downtime.

So I want floating ISCSI targets in effect.

I have just started looking into Windows ISCSI target server and was wondering if that will do the job ie. running a different
FCM on the head units but from my initial reading it seems to suggests that each node in the FCM would use different ISCSI targets which is not really what I want.

My concern is that with each head unit active and each head unit having access to the same volume on the MD3220 that there could be data corruption.

Is there a possibility of this and if so are there are any alternatives, suggestions etc. that would help.

As you may be able to tell I am not really a storage person so some of the above terminology may be a mixed up :)

Any and all help appreciated.

Jon

Hyper-V
Hyper-V
A Windows technology providing a hypervisor-based virtualization solution enabling customers to consolidate workloads onto a single server.
2,735 questions
Accepted answer
  1. TimCerling(ret) 1,156 Reputation points
    2020-09-17T13:13:55.083+00:00

    I'm a bit confused by your terminology. I've been working with clusters since they first came out, and I have never heard the term 'head unit', so I'm trying to interpret what you mean by that. From your description, it sounds like what you want is to have a two-node cluster connected to the MD3220. Are the two servers in the two-node cluster what you are calling the 'head units'?

    If this is what you mean by the 'head units', you would have a simple file serving cluster. But, instead of simply using SMB for access to the file server, you want to use iSCSi to access the file services? It would be much simpler to use SMB. I am not aware of any way for Microsoft failover clustering shared storage to be presented as Microsoft iSCSI targets as shared disks. But, once you have connected the MD3220 to a cluster, it is a simple task to present that storage as highly available SMB resources that would have the same or better performance than any iSCSI resource.

    0 comments

4 additional answers

Sort by: Most helpful
Most helpful Newest Oldest
  1. Jon Marshall 81 Reputation points
    2020-09-17T08:27:08.657+00:00

    Hi Mike

    Sorry no, should have been more specific - FCM as in Failover Cluster Manager.

    Jon

    0 comments
  2. Jon Marshall 81 Reputation points
    2020-09-17T13:44:17.27+00:00

    Hi Tim

    Thanks for the response.

    So we have a Failover Cluster of 3 hypervisors running Hyper-V, and on the backend they use 2 x 10Gbps NICs connected to 2 x 10Gbps switch. There are 2 x Dell 420s which also have 2 x 10Gbps NICs connected to the same switches.

    These Dell 420s also have SAS cables connecting to the MD3220 powervault. The Dell 420s are what I am referring to as head units (simply because that is the server guys I work with are calling them).

    I am not tied to ISCSI, it is just what we have used before but in essence what I want is to be able to somehow have the 2 x 420s act as a pair so I have redundancy, this could be an active/active or active/standby pair.

    Are you saying I could do this with SMB then ?

    Jon

    0 comments
  3. Jon Marshall 81 Reputation points
    2020-09-18T11:48:45.273+00:00

    Tim

    Based on what you said I have done some more reading and it would appear that I can use SOFS on the 420s in an active/active setup and SMB multichannel on the hypervisors to achieve what I want unless I have misunderstood.

    Does that sound right ?

    If so am I right in assuming that even with SOFS on the 420s I still cannot achieve what I want using ISCSI ?

    Thanks

    Jon

  4. Jon Marshall 81 Reputation points
    2020-09-18T12:41:57.33+00:00

    Tim

    Yes, in terms of ISCSI that is the conclusion I am coming to as well.

    I think it is looking like SMB/SOFS active/active setup which would give me everything I need as far as i can tell.

    Many thanks for your time.

    Jon

    0 comments

Your answer

Answers can be marked as Accepted Answers by the question author, which helps users to know the answer solved the author's problem.