Disable multipathing in Windows 2008 and the SAN RRS feed

  • Question

  • I had a thread back in mid Nov to find a proper way to mirgrate an existing SAN to a new SAN with existing two nodes (live production envir).  Now I encounter a different road block and need some advice.   Our initial plan was to add a third sas card to each of the existing nodes so each node can see the new SAN along with the existing SAN.  However we found out that there is no more PCI slot available for us to add the third card.  One option we have is to disable the multpathing in our current setup so we can take an existing sas card and its sas cable and use them to connect to the new SAN.   Our two nodes are IBM x3650 and the existing SAN is IBM DS3200 and the new san is DS 3524.  Each node has two sas cards and each card has a sas cable connect directly to one of redundent controllers respectively.   We are using windows 2008 x64 enterprise.

    Since I am doing this on a live production environment.  I need to know the exact steps and details and potential danger I may need to watch out for.   I like to know the following.

    1. how to disable the multipathing

    2. before I unplug a sas cable from a node, how to configure the existing SAN that it is no longer using that cable (path). 

    3. Does this require a reboot?  do I need to schedule a downtime for this or can I do that while the systme is live?

    I believe these are  steps I need to perform before I can remove a sas cable.  If there are additional steps, please advice.  Also, please advice I need to roll everything back, is there anything I need to know.


    Ocean Deep
    Monday, December 5, 2011 9:54 PM


  • Hi,


    If you connected to a iSCSI SAN through iSCSI initiator, you can perform the following steps:


    1. Open iSCSI initiator console, proceed to Targets tab, select the target in “Discovered targets”

    2. Click Devices at the bottom of the window.

    3. In the Devices window, click MPIO…..

    4. Then you will be able to change the Load balance policy.

    5. If you choose Fail Over only, then one path is Active, another is Standby.

    6. You can select the Standby one and click Details to check it.

    7. Proceed to Targets, Properties, select the identifier of the standby path to disconnect it.

    8. Proceed to Discovery tab to remove the unneeded portals.


    This one doesn’t need a reboot.


    In your environment, you are using sas card, it is recommended that you contact your storage vendor to get the further support.



    Best Regards,

    Vincent Hu


    • Marked as answer by Vincent Hu Thursday, December 8, 2011 3:23 PM
    Tuesday, December 6, 2011 1:37 PM