LUNINFO modesense response wrong?

Hi folks,

the effect of this is cosmetic, in that we cannot obtain the space
allocated to each LUN. A user on the new version (0.6.2) of
drobo-utils using it on the PRO. He reports the following output:

for ‘drobom info luns’

lun size (GB) used PTFmt FStype:
0 2199 2000 GPT [‘EXT3’]
1 2199 0 GPT [‘EXT3’]
2 2199 0 GPT [‘EXT3’]

2000 is the total used on all three LUNS, rather than the first one.
The space is distributed among the LUNS. so the third column is inaccurate.

The third column is the response supplied by the Drobo to a
Drobo LUNINFO (not LUNINFO2) mode sense query for each LUN.
section 3.8.1 for the Drobo Management interface Protocol (DMIP) document
indicates this field is:

“The LUN Used Capacity is the used capacity of this particular LUN.”

I reproduced the behaviour on a v1 with two luns, sg1 (the second 1 TB LUN)
has 7G’s used, versus the first LUN being virtually empty. Yet all usage is
reported against the first LUN, not the second one.

root@pepino:~# df /mnt2 /mnt
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sdf1 1072622668 131224 1072491444 1% /mnt2
/dev/sdg1 1072622668 7411432 1065211236 1% /mnt

root@pepino:~# drobom info

Drobo Name: hoho Devices: /dev/sdf:/dev/sdg
Time: Mon Dec 28 10:57:08 2009

Configuration maxima: slots: 4, luns: 16, lunsize: 1 TB
Capacity (in GB): used: 10, free: 1484, total: 1494
protocol version: 0.11
SCSI emulation information:
Vendor: TRUSTED Model: Mass Storage Revision: 1.00
/dev/sdf: bus=scsi18 channel=0 id=0 lun=0 (vendor=TRUSTED , version=30527)
/dev/sdg: bus=scsi18 channel=0 id=0 lun=1 (vendor=TRUSTED , version=30527)
query slotinfo result: number of slots: 4
slot GB Model Status
0 500 ST3500830AS green
1 750 WDC WD7500AAKS-00RBA0 green
2 500 WDC WD5000AAKS-00C8A0 green
3 500 WDC WD5000AAKS-00C8A0 green
Firmware: 1.3.5
Revision: 1.252 ( 21110 ) built: Aug 31 2009,18:12:03
/dev/sdf:/dev/sdg /mnt:/mnt2 hoho 00% full - ([], 0)
query options result:
RedThreshold 95
YellowThreshold 85
lun size (GB) used PTFmt FStype:
0 1099 10 GPT [‘EXT3’]
1 1099 0 GPT [‘EXT3’]


It appears that Drobo is not reporting the amount of space assigned to each LUN,
but reporting all space as belonging to the first LUN.

Hey Philobyte,

Nice to see you working on it still. Is it possible to manipulate individual LUNs with drobo-utils now? If I remember correctly, when I tested, it only did operations on “the entire Drobo” i.e. I could not erase a single LUN or add another one.

manual lun management is one of the few firmware features I haven’t implemented.
Without a device to play with, it’s quite painful. It took about 4 months (with a lot of great help from very patient people on the net) to get the rest of the settings to work. I think the only other one is ‘shutdown’ feature, whose point I fail to grok (I implemented Standby, which is all there is in older drobos, long ago, and called that shutdown.

If someone who has the device wants to code it up, I can give pretty strong hints.