diskinfo: from where it gets disks information !!

[NTC]

Hi All,
i was curious to know from where diskinfo reads the disks information in case the disk info is not in the /etc/disktab and not in the pd_infodev.tx??
If it brings the information from a patch, how to know which patch contains the disk information!!!...
i have an Hp700 machine with UX 11.11 on it...

Thx & Regards
Souheil

[Sridhar Bhaskarla]

I do not believe diskinfo looks at /etc/disktab anymore. It directly queries the disk and gets the information. Sometimes diskinfo prints the information that is already cached in the memory. So, you may see diskinfo working even if the disk is bad.

-Sri

[John Dvorchak]

From what I can find out, diskinfo reads the vendor information directly from the disk. I don't know if the information is stored in a BIOS/ROM or directly from platter(s).

[harry d brown jr]

Try this:
http://h21007.www2.hp.com/dspp/tech/tech_TechDocumentDetailPage_IDX/1,1701,2572,00.html

live free or die
harry

[Paul Sperry]

From the diskinfo man page:

For non-HP devices, diskinfo may be unable to interpret all
of the data returned by the device.

So I would say that it does not read from a file but actually gets the data from the device

[NTC]

Thanx guys for ur replies,but if diskinfo reads information from the device how it comes sometimes it detetcs wrong disk capacity!!! and what is the role of the patches in detecting new disks...

[Frank Slootweg · Accepted solution]

As others have mentioned, /etc/disktab is not used anymore (on 10.X and later).

diskinfo(1M) gets its information from the *controller* of/in the disk drive, *not* from the disk *media*.

As to why diskinfo sometimes reports incorrect size infoamtion: Because the disk is 'broken', i.e. defective, wrong/incompatible controller, wrong/incompatible firmware, etc..

Patches for detecting the right disk (size) should normally only be needed for *SAM*, not for command-line commands.

The sequence I use/recommend is:
- Does ioscan see the disk (controller)?
- Does diskinfo see the disk (controller)?
- Can "dd if=/dev/rdsk/c?d?t? of=/dev/null bs=64k count=10" read from the disk?
- Does "pvdisplay /dev/dsk/c?d?t?" indicate that this is a LVM disk?

If an earlier step does not work, you don't have to bother with the next one.