I am new to Linux, so forgive any obvious missteps or yhr use of incorrect terms. With that , here is my problem:
- HP DL580 G8, four quad-core X7350s, 128GB of ram
- RHEL 4 update 4, 64-bit, installed yesterday
- EMC Clariion cx3-40, f/w revision 3.26.40.5.010, PROM revision 3.58.0
- 16 RAID 0 LUNs, 8 assigned to each controller
- QLA2432 (2462) 4Gb FC card;
- qla2xxx-v8.01.07.15-2 driver, compiled on the system

I cannot access the LUNs on controller B. In dmesg, I see the following for the controller A LUNs:

Attached scsi disk sdk at scsi0, channel 0, id 5, lun 6
Vendor: DGC Model: RAID 0 Rev: 0326
Type: Direct-Access ANSI SCSI revision: 04
qla2400 0000:1c:00.0: scsi(0:0:5:7): Enabled tagged queuing, queue depth 32.
SCSI device sdl: 786432000 512-byte hdwr sectors (402653 MB)
SCSI device sdl: drive cache: write through
SCSI device sdl: 786432000 512-byte hdwr sectors (402653 MB)
SCSI device sdl: drive cache: write through
sdl: sdl1 sdl2 sdl3 sdl4 < sdl5 sdl6 sdl7 sdl8 sdl9 sdl10 sdl11 sdl12 sdl13 sdl14 >
Attached scsi disk sdl at scsi0, channel 0, id 5, lun 7

But for the next LUN, on controller B, I see:

Vendor: DGC Model: RAID 0 Rev: 0326
Type: Direct-Access ANSI SCSI revision: 04
qla2400 0000:1c:00.0: scsi(0:0:5:: Enabled tagged queuing, queue
depth 32.
SCSI device sdm: 838860800 512-byte hdwr sectors (429497 MB)
sdm: asking for cache data failed
sdm: assuming drive cache: write through
SCSI device sdm: 838860800 512-byte hdwr sectors (429497 MB)
sdm: asking for cache data failed
sdm: assuming drive cache: write through
sdm:<6>Device sdm not ready.
end_request: I/O error, dev sdm, sector 0
Buffer I/O error on device sdm, logical block 0
Device sdm not ready.
end_request: I/O error, dev sdm, sector 0
Buffer I/O error on device sdm, logical block 0
Device sdm not ready.
end_request: I/O error, dev sdm, sector 0
Buffer I/O error on device sdm, logical block 0
unable to read partition table
Attached scsi disk sdm at scsi0, channel 0, id 5, lun 8

There is an entry in /proc/partitions for /dev/sdm, and /dev/sdm correctly responds to scsi_id, but there is no sign of its partitions in /proc/partitions, and I cannot dd from /dev/sdm, etc.

8 176 393216000 sdl
8 177 13663282 sdl1
8 178 2739082 sdl2
8 179 2739082 sdl3
8 180 1 sdl4
8 181 2739082 sdl5
8 182 2739082 sdl6
8 183 13229527 sdl7
8 184 4409842 sdl8
8 185 4409842 sdl9
8 186 23470964 sdl10
8 187 29366819 sdl11
8 188 29366819 sdl12
8 189 29366819 sdl13
8 190 29366819 sdl14
8 192 419430400 sdm


If I trespass the LUNs from controller B and move them all to controller A, all is well. Also, if I boot up with RHEL 5 from a different partition, I can split the LUNs between the two controllers.

I installed the multipath package device-mapper-multipath-0.4.5-27.el4_6.3.x86_64.rpm, and that didn't help. I found that no matter what I did, the system never discovered two paths for
any of the LUNs for me to worry about picking the right one.

I installed RHEL5 Update 1 in another partition, and that works fine: i.e., I can move the LUNs between controllers, and as long as I reboot, it comes up and sees all the LUNs and their partitions. (I cannot use RHEL5 because of Oracle )

What am I doing wrong?

Thanks,
Reza Taheri

Does seem odd. I know in the old days Redhat rpm kernels use to leave the multi lun support off in the kernel. I am not sure of any way of telling other than looking at the config file in /boot for the kernel you have installed. Look for ' CONFIG_SCSI_MULTI_LUN ' in it an see if it is set to no. If so then you will need to recompile the kernel and set to y to be built into the kernel. Does not work as module from what I seemed to read somewhere.

Brian