how to identify the alternate link from ioscan output?

[Guna_2]

Hi all,

I am looking a server from remote site. I want to know the harddisk's alternate link detail. From ioscan output i couldn't find that...

Can any one please help me?

Regards
--MGP--

[Hemmetter]

Hi MGP

First approach simply do:
# vgdisplay -v | grep "PV Name"

But this shows only pathes that are part of a volume group.

another way is to compare PV-IDs as done by "cmpdisks"-tool

see: http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=409786

rgds
HGH

[Steven E. Protter · Accepted solution]

Shalom,

Eyeball analsysis.

iocsan sees disks. An alternate link is just a disk.

The hardware path on disks presented to an HBA is generally longer.

To be certain, you'd want to run pvdisplay on the disk device output of ioscan, when you see two disks exactly the same size, you've found your alternat path disk.

SEP

[Guna_2]

Hi

Take a example, If u we have not even created the PV. Then how can we identify?

Regards
--MGP--

[Hemmetter]

Hi MGP,

another way may be ( for EMC-devices and others)
inq.hpux from (ftp://ftp.emc.com/pub/symm3000/inquiry/)

here you can identify disks by serial number.

rgds
HGH

[Senthil Kumar .A_1]

Hi,

For ioscan it does not really matter whether a path is alternative link or not. As SEP pointed out, it just sees it as another disk. If you want to trace the alternate links, you need to be using the array related commands which queries the storage for the drive signature.

example of array related commands are,

hdsinfo -a ; for hitachi related storages
evainfo -a ; For HP eva related arrays
xpinfo ; For HP XP related storages
sympd ; For EMC related arrays

These commands might be available depending upon whether the extesion or CLI products where installed for these arrays.

SK

[Arun Jain]

hi MGP

if ioscan command is not working you can use lvlnboot command to see which is the bootable disk if you want to work on the primary hdd and if you want all the info then you can use print_manifest command but this command will work with root access only....

all the best

[Vivek_Pendse]

You can get it by this command:
Also if you install autopath which comes in os cd /dvd; will show you the bunch of links belonging to a single lun.

# vgdisplay -v vg02
--- Volume groups ---
VG Name /dev/vg02
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 4
Open LV 4
Max PV 16
Cur PV 1
Act PV 1
Max PE per PV 2047
VGDA 2
PE Size (Mbytes) 4
Total PE 2047
Alloc PE 2000
Free PE 47
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

--- Logical volumes ---
LV Name /dev/vg02/lvol14
LV Status available/syncd
LV Size (Mbytes) 2000
Current LE 500
Allocated PE 500
Used PV 1

LV Name /dev/vg02/lvol15
LV Status available/syncd
LV Size (Mbytes) 2000
Current LE 500
Allocated PE 500
Used PV 1

LV Name /dev/vg02/lvol16
LV Status available/syncd
LV Size (Mbytes) 2000
Current LE 500
Allocated PE 500
Used PV 1

LV Name /dev/vg02/lvol17
LV Status available/syncd
LV Size (Mbytes) 2000
Current LE 500
Allocated PE 500
Used PV 1


--- Physical volumes ---
PV Name /dev/dsk/c12t0d2
PV Name /dev/dsk/c13t0d2 Alternate Link
PV Name /dev/dsk/c14t0d2 Alternate Link
PV Name /dev/dsk/c15t0d2 Alternate Link
PV Name /dev/dsk/c16t0d2 Alternate Link
PV Name /dev/dsk/c17t0d2 Alternate Link
PV Name /dev/dsk/c18t0d2 Alternate Link
PV Name /dev/dsk/c19t0d2 Alternate Link
PV Status available
Total PE 2047
Free PE 47
Autoswitch On


#
Thanks,
Vivek

[Guna_2]

Hi,

From all of your reply, i could understand one think its difficult to identify the alternate link without having pv created.

And if we have storage we can use the vendors utility.

diskinfo doesn't shows the harddisks serial no. How can we get the serial no of a harddisk(internal disk or SAN)?

Thanks for all of ur reply
MGP

[Sandman!]

From ioscan or cstm you should be able to identify the serial number of the internal disk.