Topic
  • 4 replies
  • Latest Post - ‏2019-03-01T20:12:51Z by Jack0fAll
Jack0fAll
Jack0fAll
7 Posts

Pinned topic Replace gpfs disk with one of a bigger size

‏2019-02-26T17:53:06Z |

Hi all,

I'd like to know the steps to replace an in-use NSD with a bigger one. I've a 128 gb NSD that's part of a GPFS mount point and the requirement is to replace it with a 512 gb size NSD. I'd like to know the best practice for doing so. The smaller size disk would then be removed from the gpfs filesystem, zoned off the server, and eventually reclaimed by the storage team.

thanks

  • oester
    oester
    259 Posts
    ACCEPTED ANSWER

    Re: Replace gpfs disk with one of a bigger size

    ‏2019-02-26T18:16:49Z  

    What I would do is create your new NSD, add it to the file systems (mmcrnsd, mmadddisk). Then, suspend the old NSD "mmchdisk <filesystem> suspend -d old_nsd" and then use mmrestripefs "mmrestripefs <filesystem> -r" to move the data off the old NSD. Finally, use "mmdelnsd old_nsd".

    You can also use mmrpldisk, which automates things a bit - I'm old school and segmenting things give you a bit more control.

     

    Bob Oesterlin

    Nuance Communications.

  • oester
    oester
    259 Posts

    Re: Replace gpfs disk with one of a bigger size

    ‏2019-02-26T18:16:49Z  

    What I would do is create your new NSD, add it to the file systems (mmcrnsd, mmadddisk). Then, suspend the old NSD "mmchdisk <filesystem> suspend -d old_nsd" and then use mmrestripefs "mmrestripefs <filesystem> -r" to move the data off the old NSD. Finally, use "mmdelnsd old_nsd".

    You can also use mmrpldisk, which automates things a bit - I'm old school and segmenting things give you a bit more control.

     

    Bob Oesterlin

    Nuance Communications.

  • Jack0fAll
    Jack0fAll
    7 Posts

    Re: Replace gpfs disk with one of a bigger size

    ‏2019-02-26T19:36:01Z  
    • oester
    • ‏2019-02-26T18:16:49Z

    What I would do is create your new NSD, add it to the file systems (mmcrnsd, mmadddisk). Then, suspend the old NSD "mmchdisk <filesystem> suspend -d old_nsd" and then use mmrestripefs "mmrestripefs <filesystem> -r" to move the data off the old NSD. Finally, use "mmdelnsd old_nsd".

    You can also use mmrpldisk, which automates things a bit - I'm old school and segmenting things give you a bit more control.

     

    Bob Oesterlin

    Nuance Communications.

    Thank you so very much oester.

    I too would like to know the steps to follow instead of running a single command "mmrpldisk".

    And all of this can be done online i.e. no need to un-mount the gpfs filesystem or stop the cluster, correct?

  • oester
    oester
    259 Posts

    Re: Replace gpfs disk with one of a bigger size

    ‏2019-02-26T19:38:36Z  
    • Jack0fAll
    • ‏2019-02-26T19:36:01Z

    Thank you so very much oester.

    I too would like to know the steps to follow instead of running a single command "mmrpldisk".

    And all of this can be done online i.e. no need to un-mount the gpfs filesystem or stop the cluster, correct?

    Correct - you may experience some IO degradation (impact) while the data blocks are moved. But the file system will remain available.

     

    Bob

  • Jack0fAll
    Jack0fAll
    7 Posts

    Re: Replace gpfs disk with one of a bigger size

    ‏2019-03-01T20:12:51Z  
    • oester
    • ‏2019-02-26T19:38:36Z

    Correct - you may experience some IO degradation (impact) while the data blocks are moved. But the file system will remain available.

     

    Bob

    Great thank you!