Topics: AIX, EMC, SAN, Storage, System Admin

Unable to remove hdiskpower devices due to a method error

If you get a method error when trying to rmdev -dl your hdiskpower devices, then follow this procedure.

Cannot remove hdiskpower devices with rmdev, get error "method error (/etc/methods/ucfgpowerdisk):"
The fix is to uninstall/reinstall Powerpath, but you won't be able to until you remove the hdiskpower devices with this procedure:
  1. # odmdelete -q name=hdiskpowerX -o CuDv
    (for every hdiskpower device)
  2. # odmdelete -q name=hdiskpowerX -o CuAt
    (for every hdiskpower device)
  3. # odmdelete -q name=powerpath0 -o CuDv
  4. # odmdelete -q name=powerpath0 -o CuAt
  5. # rm /dev/powerpath0
  6. You must remove the modified files installed by powerpath and then reboot the server. You will then be able to uninstall powerpath after the reboot via the "installp -u EMCpower" command. The files to be removed are as follows:

    (Do not be concerned if some of the removals do not work as PowerPath may not be fully configured properly).
    # rm ./etc/PowerPathExtensions
    # rm ./etc/emcp_registration
    # rm ./usr/lib/boot/protoext/disk.proto.ext.scsi.pseudo.power
    # rm ./usr/lib/drivers/pnext
    # rm ./usr/lib/drivers/powerdd
    # rm ./usr/lib/drivers/powerdiskdd
    # rm ./usr/lib/libpn.a
    # rm ./usr/lib/methods/cfgpower
    # rm ./usr/lib/methods/cfgpowerdisk
    # rm ./usr/lib/methods/chgpowerdisk
    # rm ./usr/lib/methods/
    # rm ./usr/lib/methods/ucfgpower
    # rm ./usr/lib/methods/ucfgpowerdisk
    # rm ./usr/lib/nls/msg/en_US/
    # rm ./usr/sbin/powercf
    # rm ./usr/sbin/powerprotect
    # rm ./usr/sbin/pprootdev
    # rm ./usr/lib/drivers/cgext
    # rm ./usr/lib/drivers/mpcext
    # rm ./usr/lib/
    # rm ./usr/lib/
    # rm ./usr/lib/
    # rm ./usr/lib/drivers/mpext
    # rm ./usr/lib/libmp.a
    # rm ./usr/sbin/emcpreg
    # rm ./usr/sbin/powermt
    # rm ./usr/share/man/man1/emcpreg.1
    # rm ./usr/share/man/man1/powermt.1
    # rm ./usr/share/man/man1/powerprotect.1
  7. Re-install Powerpath.

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