identifying disk

[madhudeepan]

once i went in data center room,,, i have a doubt in that

how do identify the primary disk and secondary disk since there were large no of disks

[Ganesan R]

Hi Madhudeepan,

You cannot identify the primary and secondary disk by looking physically.

Use lvlnboot -v command which will give you the primary/seconday disks and it's hardware paths. Using the hardware path you can locate the disks.

[madhudeepan]

i think there is a option to find it,, by giving dd cmd or some other cmd [i dont remember exactly ] led will blink on disk,,

so that we can identify


but i am not sure ,,

[Lijeesh N G_1]

Hi Madhudeepan,

You can find the boot disk(Presently booted)from the following outputs,

# dmesg|grep -i boot
Boot device's HP-UX HW path is: 0/1/1/0.1.0

# ioscan -fnH 0/1/1/0.1.0
Class I H/W Path Driver S/W State H/W Type Description
=====================================================================
disk 2 0/1/1/0.1.0 sdisk CLAIMED DEVICE HP 146 GMAP3147NC
/dev/dsk/c2t1d0 /dev/rdsk/c2t1d0
/dev/dsk/c2t1d0s1 /dev/rdsk/c2t1d0s1
/dev/dsk/c2t1d0s2 /dev/rdsk/c2t1d0s2
/dev/dsk/c2t1d0s3 /dev/rdsk/c2t1d0s3
===========================================

For finding Primary /Secondary boot deivice you use the following commnd,
# setboot
Primary bootpath : 0/1/1/0.1.0
HA Alternate bootpath :
Alternate bootpath : 0

Autoboot is ON (enabled)
---------------------------------------
Regards
LIJEESH N G

[Lijeesh N G_1]

Hi,

Since as you told there are larger no. of disks,with dd command it is difficult to find out the disk physically.

If you want to use dd command, 1st you have to find out the device file of the disk,
using the device file run the follwing command;

#dd if=/dev/rdsk/ of=/dev/null bs=1024 count=50

Eg.dd if=/dev/rdsk/c2t1d0 of=/dev/null bs=1024 count=50
50+0 records in
50+0 records out


It will read 1024 blocks of data 50 times from the disk,
that time there will be LED blinking on the particular disk.


Regards,
LIJEESH N G

[Suraj K Sankari]

HI,
Physically looking to the server you cannot identify the primary and secondary disk for that you need to login into the server and run this command.

lvlnboot -v
dmesg | grep -i boot # you can find the primary disk

Suraj

[nobleboi]

i suggest do not go to the data centre, and u ll have no doubt :)

[SoorajCleris]

Hi,

I think you heared about UID ( unit identification which is called locator LED).

It is not avaialable for HDD it is available for servers and some case PCI slots ( I am not sure, heared OLAR uses). So that administrator can locate the servers in huge data centres.

Regards,
Sooraj