Total PE not same in 2 disk

[j773303]

Hello Expert,
I've a question about the Total PE not same in the 2 same disk. Following are the 2 disk information, on Total PE is 4340, another is 4350. Can anyone knows how to explaiin this?
Is it correct? Thanks.



HP 73.4GST373453LW
HP 73.4GST373207LW

wtiptop:/#diskinfo -v /dev/rdsk/c0t5d0
SCSI describe of /dev/rdsk/c0t5d0:
vendor: HP 73.4G
product id: ST373453LW
type: direct access
size: 71687369 Kbytes
bytes per sector: 512
rev level: HPC3
blocks per disk: 143374738
ISO version: 0
ECMA version: 0
ANSI version: 3
removable media: no
response format: 2

gwtiptop:/#diskinfo -v /dev/rdsk/c0t6d0
SCSI describe of /dev/rdsk/c0t6d0:
vendor: HP 73.4G
product id: ST373207LW
type: direct access
size: 71687369 Kbytes
bytes per sector: 512
rev level: HPC1
blocks per disk: 143374738
ISO version: 0
ECMA version: 0
ANSI version: 3
removable media: no
response format: 2

--- Physical volumes ---
PV Name /dev/dsk/c0t6d0
PV Status available
Total PE 4340
Free PE 298
Autoswitch On

PV Name /dev/dsk/c0t5d0
PV Status available
Total PE 4350
Free PE 308
Autoswitch On

[Bill Hassell · Accepted solution]

Although the blocks per disk and size in Kbytes are the same, the firmware revision is different as well as the model number:

product id: ST373453LW
rev level: HPC3
product id: ST373207LW
rev level: HPC1

So these disks are indeed different. Disk manufacturers have widely varied designs that affect the available sectors reported by the firmware. Although they appear similar, they are different disks internally which may include handling of the inner and outer tracks, and the spare tracks. These disks will be fine to mirror to each other but limit the total size to the smaller size and forget the 10 extra PEs. If they aren't going to be mirrored, just use the all the PEs.