Forum Discussion

liuyl's avatar
liuyl
Level 6
6 years ago

The behavior of VxDMP when one of its multi-path down

When we test the VxDMP 5/6 with default minimumq for both VxVM and LVM via the same HDS G1K and vxbench program on AIX 5/6, a strange phenomenon appeared！
That is, once one of the VxDMP for VxVM multipath was broken down, the I/Os of all the others good links would hang up with for a short time(15s). versus the VxDMP for native LVM would contiune the remaining I/Os of all the others good links wittout any disruption！ 

So how to explain such phenomenon？

  • frankgfan's avatar
    frankgfan
    Moderator
    6 years ago

    there are many parameters and tunables for Vxvm, dmp and scsi controllers.

    https://sort.veritas.com/public/documents/dmp/5.1sp1/aix/productguides/html/dmp_admin/ch08s02.htm

    https://sort.veritas.com/public/documents/sfha/6.0/linux/productguides/html/sf_admin/ch32s02s02s01.htm

    If you are not very familiar with tuing vxvm/dmp and troubleshooting the issue, collect the data below and log a support case with veritas.

    1. a detailed description of your tests (including the names of the volumes and file systems involved)

    2. VRTSexplorer(DataCollector) report

    3. Firstlook report (must be collected during the tests.  https://www.veritas.com/support/en_US/article.000038518)

    Likely an escalation of the case is required.

    Cheers,

    Frank

     

    • liuyl's avatar
      liuyl
      Level 6
      6 years ago

      It is too unfortunate that the case problem has almost sustained for one year,  but still not resolved！
      My local region technical support is so weaker that they could only admit the fact at last,  but could not give any more reasonable explanation！

      Note: or if you prefer, I shall give you the CASE ID ！

      • frankgfan's avatar
        frankgfan
        Moderator
        6 years ago

        Do this without delay.

        Call Veritas support hotline during Australia business hours and request the case to be escalated to a backlineline immediately.

        Before calling, make sure that you have collected the data that I requested you to collect in my previous node. 

        Of course you need to check and make sure your hardware is supporetd https://sort.veritas.com/hcl

        You can also send me the case ID

  • Marianne's avatar
    Marianne
    Level 6
    6 years ago

    liuyl

    If you believe there is a problem with VxDMP, then please log a call with Veritas Support.

    They will need to analyze your config and logs to see why this happens.

    Your experience is certainly not normal.