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
Details:
-sdgs 32g
Growth Increment. Note: use32g
instead of32768
!-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
Filter-pattern-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
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