To migrate to thin provisioning

1. Turn on the SmartMove feature. Edit the /etc/default/vxsf file so that usefssmartmove is set to all.

   usefssmartmove=all

2. Add the new, thin LUNs to the existing disk group:

   # vxdisksetup -I da_name

   # vxdg -g datadg adddisk da_name

   where da_name is the disk access name in VxVM.

   If enclosure based naming (EBN) is enabled and the disk accesss name is displayed, enter:

   # vxddladm set naming scheme=ebn

3. To identify thin LUNs, enter:

   # vxdisk -o thin list

4. Add the new, thin LUNs as a new plex to the volume.

   NOTE: The VxFS file system must be mounted to get the benefits of the SmartMove feature.

   The following methods are available to add the LUNs:

   • Use the default settings:

     # vxassist -g datadg mirror datavol da_name

   • Use the options for fast completion. The following command has more I/O impact.

     # vxassist -b -oiosize=1m -t thinmig -g datadg mirror \
       datavol da_name

     # vxtask monitor thinmig

     TASKID  PTID TYPE/STATE    PCT     PROGRESS
     167          ATCOPY/R      00.34%  0/73400320/252416 PLXATT datavol datavol-02 datadg
     167          ATCOPY/R      00.35%  0/73400320/259840 PLXATT datavol datavol-02 datadg
     167          ATCOPY/R      00.36%  0/73400320/267264 PLXATT datavol datavol-02 datadg

   • Use the options for minimal impact. The following command takes longer to complete:

     # vxassist -oslow -g datadg mirror datavol da_name

5. Optionally, test the performance of the new LUNs before removing the old LUNs.

   To test the performance, use the following steps:

   • Determine which plex corresponds to the thin LUNs:

     # vxprint -g datadg

     TY NAME         	     ASSOC   	       KSTATE   LENGTH     PLOFFS  STATE     TUTIL0 PUTIL0
     dg datadg       	     datadg      	   -        -          -       -         -       -
     dm THINARRAY0_02      THINARRAY0_02   -      	 83886080   -       -         -       -
     dm STDARRAY1_01	      STDARRAY1_01    -  	     41943040   -       -OHOTUSE  -       -
     
     v  datavol      	     fsgen        	  ENABLED 	41943040   -       ACTIVE    -       -
     pl datavol-01   	     datavol      	  ENABLED 	41943040   -       ACTIVE    -       -
     sd STDARRAY1_01-01    datavol-01   	  ENABLED 	41943040   0       -         -       -
     pl datavol-02   	     datavol      	  ENABLED 	41943040   -       ACTIVE    -       -
     sd THINARRAY0_02-01   datavol-02   	  ENABLED 	41943040   0       -         -       -

     The above output indicates that the thin LUNs corresponds to plex datavol-02.

   • Direct all reads to come from those LUNs:

     # vxvol -g datadg rdpol prefer datavol datavol-02

6. Remove the original non-thin LUNs.

   Note:

   The ! character is a special character in some shells. This example shows how to escape it in a bash shell.

   # vxassist -g datadg remove mirror datavol \!STDARRAY1_01

   # vxdg -g datadg rmdisk STDARRAY1_01

   # vxdisk rm STDARRAY1_01

7. Grow the file system and volume to use all of the larger thin LUN:

   # vxresize -g datadg -x datavol 40g da_name