topic Re: Finding the unallocated-disks/Free-disks. in Operating System - HP-UX

Finding the unallocated-disks/Free-disks.

sudhapage — Thu, 11 Sep 2008 05:51:42 GMT

Hi All,

How to find the unallocated-disks/Free-disks in hpux.

That disk should be part of LVM/VERITAS/ORACLE RAW FILESYSTEM.

Please suggest.

Regards,
Sudhakaran.K

Re: Finding the unallocated-disks/Free-disks.

Sandeep_Chaudhary — Thu, 11 Sep 2008 06:04:08 GMT

run "ioscan -funCdisk" to find disks available in machine

If the disk is not yet used in LVM then u get following output

suxde034 # pvdisplay /dev/dsk/c17t1d0
pvdisplay: Couldn't find the volume group to which
physical volume "/dev/dsk/c17t1d0" belongs.

If the disk is/was part of LVM use

suxde900 # pvdisplay /dev/dsk/c3t1d0
--- Physical volumes ---
PV Name /dev/dsk/c3t1d0
VG Name /dev/vg01
PV Status available
Allocatable yes
VGDA 2
Cur LV 1
PE Size (Mbytes) 4
Total PE 2169
Free PE 1418
Allocated PE 751
Stale PE 0
IO Timeout (Seconds) default
Autoswitch On

here u can look for

Total PE 2169
Free PE 1418
Allocated PE 751
If "total PE" and "Free PE" are same means though disk is part of LVM it is free

another way is vgdisplay -v vgname
at the end u get disks the VG is having and its PE statistics

for ex:
PV Name /dev/dsk/c3t1d0
PV Status available
Total PE 2169
Free PE 1418
Autoswitch On

here "Total PE" and "free PE" are not matching means disk is used.

IS this what u expected?

Re: Finding the unallocated-disks/Free-disks.

Prashanth Waugh — Thu, 11 Sep 2008 06:08:15 GMT

Hi Sudha,

#strings /etc/lvmtab | grep "cntndn"

If its not a part of lvmtab means this disk is free on server. it is not used anywhere.

Regards
Prashant

Re: Finding the unallocated-disks/Free-disks.

sudhapage — Thu, 11 Sep 2008 06:13:04 GMT

Hi Sandeep/Prasanth,

Thanks for the reply.

In my server, there are 400 disks are there in ioscan output. So I can't verify manually. Is there any script to verify the disks are free.

That disks should not be in LVM/Veritas/Oracle RAW format disk,etc..

Regards,
Sudhakaran.K

Re: Finding the unallocated-disks/Free-disks.

Prashanth Waugh — Thu, 11 Sep 2008 06:33:09 GMT

Hi Sudha,

/etc/lvmtab contains the all vgs and its pv respectively. so if its not a part of vg means its not part of lv.see if u r using raw FS for oracle but that raw FS is nothing but the lv. and lv will be the part of vg. its ebntry will be in /etc/lvmtab. so that disk will not be a member of raw FS

Regards
Prashant

Re: Finding the unallocated-disks/Free-disks.

sudhapage — Thu, 11 Sep 2008 08:29:07 GMT

Is there any script to list freedisks in the servers.

In our server, there 400 EMC disks are there, so I can't verify individually.

Regards,
Sudhakaran.K

Re: Finding the unallocated-disks/Free-disks.

Duncan Edmonstone — Thu, 11 Sep 2008 09:00:09 GMT

Hi,

If you have VxVM initialized on your system then,

vxdisk list

should show you at least VxVM and LVM disks - I'm not sure whether it can identify raw Oracle disks, Oracle ASM disks or Oracle Clusterware registry/voting disks

HTH

Duncan

Re: Finding the unallocated-disks/Free-disks.

Sandeep_Chaudhary — Thu, 11 Sep 2008 09:15:35 GMT

vgdisplay -v|grep "PV Name"|awk '{print $NF}'>/tmp/lvmdisk
ioscan -funCdisk|awk '{print $NF}'|grep dev>/tmp/ioscandisk

and compare two files

Re: Finding the unallocated-disks/Free-disks.

Deepak Kr — Thu, 11 Sep 2008 11:56:16 GMT

Prashant wrote:

>>> if u r using raw FS for oracle but that raw FS is nothing but the lv.<<

It is not always true. For example Oracle 10g is capable of using disks even without sitting top of LVM.

But as suggested, getting comparison from ioscan and lvmtab will be helpful here.

If it is a prod box, go through the configuration doc if any.