topic Re: Disk ask? in Operating System - HP-UX

Disk ask?

castro_2 — Thu, 03 Apr 2003 19:35:24 GMT

bdf /u011
/dev/vg01/lvol1 17408000 14351602 2912287 83% /u011

I have this VG, when I do vgdisplay -v vg01

vgdisplay -v vg01
--- Volume groups ---
VG Name /dev/vg01
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 1
Open LV 1
Max PV 16
Cur PV 2
Act PV 2
Max PE per PV 2170
VGDA 4
PE Size (Mbytes) 4
Total PE 4339
Alloc PE 4250
Free PE 89
Total PVG 0

--- Logical volumes ---
LV Name /dev/vg01/lvol1
LV Status available/syncd
LV Size (Mbytes) 17000
Current LE 4250
Allocated PE 4250
Used PV 2

--- Physical volumes ---
PV Name /dev/dsk/c0t3d0
PV Status available
Total PE 2169
Free PE 0
Autoswitch On

PV Name /dev/dsk/c0t5d0
PV Status available
Total PE 2170
Free PE 89
Autoswitch On

It has 2 disk.
diskinfo /dev/rdsk/c0t3d0
SCSI describe of /dev/rdsk/c0t3d0:
vendor: SEAGATE
product id: ST39173WC
type: direct access
size: 8886762 Kbytes
bytes per sector: 512

diskinfo /dev/rdsk/c0t5d0
SCSI describe of /dev/rdsk/c0t5d0:
vendor: SEAGATE
product id: ST318275LC
type: direct access
size: 17783240 Kbytes
bytes per sector: 512

The Total size should be 17 GB + 8 GB = 25 GB
Why show me 17 GB.
Is hp-ux 10.20
Thanks

Re: Disk ask?

Pete Randall — Thu, 03 Apr 2003 19:42:48 GMT

Your "Max PE per PV 2170" is limiting how many 4 Mb physical extents you can have on each physical volume. In order to in crease this, you would have to recreate the vg with a larger maxPE value.

Pete

Re: Disk ask?

John Poff — Thu, 03 Apr 2003 19:45:28 GMT

Hi,

It looks like you got bitten by the maximum number of physical extents. When you created your volume group with the first 8Gb disk, it set the max PEs to 2170. The default is to use 1016 for the max PEs, but if that times the PE size [default of 4 Mb] is smaller than the PV size, the max PEs will be increased to handle the disk size. When you added the 17 Gb disk to the volume group, you really needed about twice the number of PEs to use the disk, but your VG was set for 2170 and so you could only use about 8Gb of the 17 Gb disk. To use all of the 17 Gb disk you will have to backup all the data, blow away the volume group, recreate it with both disks, picking up a bigger max physical extents number, recreate the LVs and filesystems, and restore.

JP

Re: Disk ask?

castro_2 — Thu, 03 Apr 2003 19:51:01 GMT

You 're rigth the Max PE per PV 2170, how can I do to recreate de VG.
Thanks

Re: Disk ask?

Geoff Wild — Thu, 03 Apr 2003 19:52:44 GMT

You will have to back up your data, blow away the volume group, then re-create it with a larger PE size.

Sorry...

Rgds...Geoff

Re: Disk ask?

John Poff — Thu, 03 Apr 2003 19:53:18 GMT

Hi again,

Also, your diskinfo is just looking at the individual PV, and it can see that it is a 17 Gb disk.

Maybe someday somebody will write a REALLY, REALLY Online JFS that will let us add any size disk to any volume group with no max PVs, LVs, PEs, etc. Someday. :)

JP

Re: Disk ask?

Marco Santerre — Thu, 03 Apr 2003 20:00:59 GMT

Unfortunately, you don't have many choices but to :

1) Backup all your data
2) vgexport vg01
3) mkdir /dev/vg01
4) mknod /dev/vg01/group c 64 0xnn0000 {where nn is a major number that hasn't been used already}
5) PVcreate your disks
6) one of these two :
vgcreate -e 4400 /dev/vg01 /dev/dsk/c0t5d0 or
vgcreate vg01 /dev/dsk/c0t5d0
7) vgextend vg01 /dev/dsk/c0t3d0
8) lvcreate -l 4250 -n lvol1 vg01
9) newfs -F vxfs /dev/vg01/rlvol1
10) mount your FS
11) Restore your data