Topic
2 replies Latest Post - ‏2014-08-21T16:21:53Z by Dave32
Dave32
Dave32
6 Posts
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Pinned topic Virtualizing a Storwize V5000 with an IBM SVC

‏2014-08-14T19:20:23Z |

I am using the storage from a Storwize V5000 behind a SAN Volume Controller.  I have 1 Controller and 5 enclosures (4 TB drives) for a total of 200+ TB's of data.  Based on this, is there a way to determine what the optimal size for volumes on the V5000 should be? 

Some additional data is that I'll be connecting to an 8 node SVC cluster as the "host".  On the V5000 I have created 8 hosts, one for each SVC node with four ports each.  When configuring the storage on the V5000 I chose the automatic option which created 72 Raid 6 disks.

Hoping someone can give some advice on what would be the best way to determine the volume size.

 

  • AndersLorensen
    AndersLorensen
    156 Posts
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    Re: Virtualizing a Storwize V5000 with an IBM SVC

    ‏2014-08-19T07:30:54Z  in response to Dave32

    You need to consider the following:

    Easyness of moving MDISKS between pools on the SVC Cluster. The smaller the MDISK the easier it is to move an MDISK around. If you create one static pool that will never increase or decrease in size, then this is irrelevant, and you might as well just present one big 200 TB volume to the SVC Cluster.

     

    Extend size - You should also make sure the extend size are the same on the pool on the V5000 and the SVC.

     

    The limits that are relevant for you:

    Max number of volumes: 2048. (meaning your minimum volume size is about 100 GB)

    Max volume size: 256 TB.

    Managed disks per storage pool: 128 (meaning if you want it all in 1 pool, your minimum size is ~2 TB.)

    Managed disks (MDisks) per system: 4096 (Relevant if the entire SVC cluster is closing in on this number)

     

    The optimal size is individual really. If your pool will stay static, never get increased or decreased in size etc. 1 volume is optimal. But few are ready to predict the future that way!. All other situations, the smaller the better, for flexibility (while staying within the limits above). Having a manageable amount of MDISKS is the key in my opinion. And then the number of volumes should be somewhere between 20 and 50 in my World. So my advice would be to go with 8 TB volumes.

     

    /Anders

    • Dave32
      Dave32
      6 Posts
      ACCEPTED ANSWER

      Re: Virtualizing a Storwize V5000 with an IBM SVC

      ‏2014-08-21T16:21:53Z  in response to AndersLorensen

      Hi Anders, thank you very much for your reply.

      Although at this point I'd like to say the pool will stay static forever, it's difficult to predict what may happen in the future so I'm a little leary of just creating one large volume.  Based on this I opted to create twenty 10.3 TB volumes.

      I appreciate your input.

      Thank you!