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  • 1.  PSP - Change from Fixed to RR

    Posted Jul 10, 2019 03:56 PM

    hi folks,

    I have many luns that are using Fixed PSP, so I want to know if it's safe to change on the fly to RR or what's the best procedure to change ?

    Regards



  • 2.  RE: PSP - Change from Fixed to RR
    Best Answer

    Posted Jul 10, 2019 04:07 PM

    1st would be to check if the RR is supported by the array as PSP.

    We can verify the same from VMware HCL as well

    VMware Compatibility Guide - Storage/SAN Search

    It's safe to change the PSP from Fixed to RR and change requires to be performed for each lun.

    Or You can change the same by changing default PSP for SATP which requires restart to get the new PSP applied for existing LUN's

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  • 3.  RE: PSP - Change from Fixed to RR

    Posted Jul 11, 2019 08:24 AM

    DeepikaG​​ thank you, i think RR is supported because not all Lun are using fixed psp. I'll try to change and give you feedback.

    Regards

    Re: PSP - Change from Fixed to RR
    DeepikaG



  • 4.  RE: PSP - Change from Fixed to RR

    Posted Jul 11, 2019 03:59 PM

    The array is on VMware HCL but i forget to mention that we use vPLEX and yes the vPlex also is on the HCL .

    So, for test, I only changed 1 lun... so far nothing wrong i I'll set RR as default tomorrow.

    I think that's all.

    Thank you



  • 5.  RE: PSP - Change from Fixed to RR

    Posted Jul 10, 2019 04:31 PM

    as mentioned by Deepika its fine to change the PSP as long as the array supports it. But its safe to do when the VMs on the respective datastore are not running. Same recommended for VMs with RDMs. Some instabilities are observed when the VMs running with applications which are IO sensitive.



  • 6.  RE: PSP - Change from Fixed to RR

    Posted Jul 11, 2019 08:26 AM

    all right, :smileyhappy: we don't use RDMs.

    Thank you