Topic
  • 4 replies
  • Latest Post - ‏2015-11-14T06:08:09Z by OneSkyWalker1
diskdur
diskdur
4 Posts

Pinned topic vscsi to npiv data migration question

‏2013-02-20T09:58:34Z |
Hi

I'm planning migration from :
source = typical dual vios + all vioc with vscsi luns remapped (rootvg+datas)
target = typical dual vios + hba 5735 + npiv + all vioc with (vscsi rootvg + npiv vfc for data luns)

New pseries will have fresh rootvg install, so no need to migrate the system disk.
About data luns, is it possible that I copy the vscsi remapped data luns with PPRC, and then present them to the target vioc vfc wwpn and do the importvg ?
Or is it the only option to do LVM ?

Thanks for your help.

dd
Updated on 2013-02-21T08:22:29Z at 2013-02-21T08:22:29Z by diskdur
  • unixgrl
    unixgrl
    25 Posts

    Re: vscsi to npiv data migration question

    ‏2013-02-20T22:53:03Z  
    I don't know what PPRC is but you have a few options.

    You can rezone the vscsi disks to the virtual WWPNs to make them visible on the new system. Make sure disk reserves are off if disks will be zoned to more than 1 system at a time.
    Once you run cfgmgr to pull them in, you should be able to import the disk groups using the new disk names. Make sure you know which LUN id goes with each disk
    group beforehand because the disk numbering is likely to change.

    If you want to convert the existing VIOC in place, you could add NPIV vfc adapters, make the vscsi disks visible to the NPIV WWNs, verify, remove the paths to vSCSI, remove the vSCSI mapping and unzone from vSCSI WWNs.

    You could also add NPIV to VIOC w/vSCSI, add brand new storage, do migratepv from vSCSI disk to NPIV, remove vSCSI disk.

    We're looking at similar conversions where I work and our process is going to depend on what the SAN team is comfortable with supporting.
  • diskdur
    diskdur
    4 Posts

    Re: vscsi to npiv data migration question

    ‏2013-02-21T07:45:09Z  
    • unixgrl
    • ‏2013-02-20T22:53:03Z
    I don't know what PPRC is but you have a few options.

    You can rezone the vscsi disks to the virtual WWPNs to make them visible on the new system. Make sure disk reserves are off if disks will be zoned to more than 1 system at a time.
    Once you run cfgmgr to pull them in, you should be able to import the disk groups using the new disk names. Make sure you know which LUN id goes with each disk
    group beforehand because the disk numbering is likely to change.

    If you want to convert the existing VIOC in place, you could add NPIV vfc adapters, make the vscsi disks visible to the NPIV WWNs, verify, remove the paths to vSCSI, remove the vSCSI mapping and unzone from vSCSI WWNs.

    You could also add NPIV to VIOC w/vSCSI, add brand new storage, do migratepv from vSCSI disk to NPIV, remove vSCSI disk.

    We're looking at similar conversions where I work and our process is going to depend on what the SAN team is comfortable with supporting.
    Thanks for your reply. Appreciated.

    PPRC is IBM block device replication included in IBM SAN Storage arrays http://www.redbooks.ibm.com/abstracts/sg246568.html. It is like EMC SRDF or Hitachi TrueCopy, 2 san arrays are logically connected to each other, and they copy luns from one to the other.

    From what you explained, it seems that the answer to my question could be PPRC is OK.
    But I really need to be sure of that.

    Are your sure that you can just zone a previously vscsi lun to a vfc wwpn, and vgimport will work ?
    If the vios have added some kind of encapsulation data on the lun, it won't work according to me.
    As I don't know if the vios write something on the physical disk, it's difficult to conclude...
  • diskdur
    diskdur
    4 Posts

    Re: vscsi to npiv data migration question

    ‏2013-02-21T08:22:29Z  
    • diskdur
    • ‏2013-02-21T07:45:09Z
    Thanks for your reply. Appreciated.

    PPRC is IBM block device replication included in IBM SAN Storage arrays http://www.redbooks.ibm.com/abstracts/sg246568.html. It is like EMC SRDF or Hitachi TrueCopy, 2 san arrays are logically connected to each other, and they copy luns from one to the other.

    From what you explained, it seems that the answer to my question could be PPRC is OK.
    But I really need to be sure of that.

    Are your sure that you can just zone a previously vscsi lun to a vfc wwpn, and vgimport will work ?
    If the vios have added some kind of encapsulation data on the lun, it won't work according to me.
    As I don't know if the vios write something on the physical disk, it's difficult to conclude...
    According to this interesting redbook, it seems to be OK with some conditions.

    http://www.redbooks.ibm.com/redbooks/pdfs/sg247825.pdf
  • OneSkyWalker1
    OneSkyWalker1
    2 Posts

    Re: vscsi to npiv data migration question

    ‏2015-11-14T06:08:09Z  
    • unixgrl
    • ‏2013-02-20T22:53:03Z
    I don't know what PPRC is but you have a few options.

    You can rezone the vscsi disks to the virtual WWPNs to make them visible on the new system. Make sure disk reserves are off if disks will be zoned to more than 1 system at a time.
    Once you run cfgmgr to pull them in, you should be able to import the disk groups using the new disk names. Make sure you know which LUN id goes with each disk
    group beforehand because the disk numbering is likely to change.

    If you want to convert the existing VIOC in place, you could add NPIV vfc adapters, make the vscsi disks visible to the NPIV WWNs, verify, remove the paths to vSCSI, remove the vSCSI mapping and unzone from vSCSI WWNs.

    You could also add NPIV to VIOC w/vSCSI, add brand new storage, do migratepv from vSCSI disk to NPIV, remove vSCSI disk.

    We're looking at similar conversions where I work and our process is going to depend on what the SAN team is comfortable with supporting.

    Just to provide a single data point here.

    I had trouble installing RHEL 7.1 on Power Systems on a single 80 GB LUN accessed via virtual Fibre Channel.  Please see the Install fails with "partition is too large for PPC PReP Boot formatting" post for more detail regarding the problem I encountered.

    I circumvented the problem by reconfiguring the LUN to be accessed via virtual SCSI via a single VIO Server.  I was then able to install RHEL 7.1.

    Once the install completed successfully, I shut the RHEL 7.1 LPAR down, reconfigured the RHEL 7.1 boot disk to be accessed via two virtual Fibre Channel devices, booted the LPAR up into SMS mode, located the virtual Fibre Channel boot disk, booted from it, and RHEL 7.1 came up with no problem.  I then updated the bootlist with 'bootlist -m normal sda sdb sdc sdd'.

    Updated on 2016-04-01T16:33:19Z at 2016-04-01T16:33:19Z by OneSkyWalker1