Create CPG using Disk Filter

Create CPG using Disk Filter

Recently I had to create a new 3PAR CPG using just new added 1.2TB disks. But the system uses already a cage full of 600GB disk. While it was straight forward to change the existing CPG (using 3PAR Management Console) – StoreServe Management Console (SSMC) does not support this feature any more) to use all disk in cage 0, it was not possible to create a new CPG for all FC disks in cage 1. It was not possible to filter cage number, slot in cage, magazine or chunklet-sizes in the GUI. Also using a simple version of createcpg command does not work. All I got was an error: “Error: no available space for given (invalid?) parameters“.

[Update] Check also my post (3PAR: Considerations when mixing sizes of same disk type) about disks of same type but different size within an array.

To get the work done, I used this command:

createcpg -sdgs 32g -t r5 -ha mag -ssz 4 -ss 128 -ch first -p -devtype FC -tc_gt 546 -saga "-ha mag -p -devtype FC -tc_gt 546" FC_r5_1200_AO


  • -sdgs 32g
    Growth Increment. Note: use 32g instead of 32768!
  • -t
    Raid-Level (r0, r1, r5, r6)
  • -ha
    Availability (port, cag, mag)
  • -ssz
    Set-size. For example: set-size of 4 when using Raid5 means 3+1
  • -ss
    Step-size (KB)
  • -ch
    Preferred chunklets (first, last)
  • -p

    • -devtype
      Disktype (FC, NL, SSD)
    • -tc_gt
      Means: “total chunklets greater than”. -tc_gt 546 selects all disk have more than 546 chunklets (size of a chunklet = 1G –> use all disks greater than 600GB)
    • -tc_lt
      Means: “total chunklets less than”.
  • -saga
    This parameter describes the admin-space of the CPG. If you don’t enter this parameter, the characteristic of the admin-space will be different to the characteristic  of the user-space.
  • FC_r5_1200_AO
    Name of the new CPG

2 responses to “Create CPG using Disk Filter”

  1. […] you have different CPGs for different disk sizes (how this can be done, you can read here), you must check before replacing a failed disk by a disk of a new size. Will the replaced disk be […]

  2. […] system (GUI or command tunesys) to remove chunklets from CPG afterwards. About disk-filter see here and […]

Leave a Reply

Your email address will not be published. Required fields are marked *