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External USB hard drive enclosure - not recognizing all drives

Hi,

I have a Venus T4U external hard drive enclosure that has two 320GB drives on IDE0 (1 master and 1 slave). The unit is configured to normal mode - each drive is treated as a separate drive, not JBOD. This is a fresh Slackware 12 install and it's only recognizing one of the drives (but I can mount it).

dmesg output:

Code:

usb 1-3: new high speed USB device using ehci_hcd and address 3

usb 1-3: configuration #1 chosen from 1 choice

scsi3 : SCSI emulation for USB Mass Storage devices

usb-storage: device found at 3

usb-storage: waiting for device to settle before scanning

kobject_add failed for usb_storage with -EEXIST, don't try to register things with the same name in the same directory.

 [<c03e86f7>] kobject_shadow_add+0x117/0x1a0

 [<c013fba4>] mod_sysfs_setup+0x24/0xb0

 [<c0141458>] sys_init_module+0x1648/0x1940

 [<c0102ae8>] syscall_call+0x7/0xb

 [<c0710000>] __mutex_lock_slowpath+0x40/0x90

 =======================

scsi 3:0:0:0: Direct-Access    WDC      WD3200SB-01KMA-1 08.0 PQ: 0 ANSI: 2

SCSI device sda: 625142448 512-byte hdwr sectors (320073 MB)

sda: Write Protect is off

sda: Mode Sense: 53 00 00 08

sda: assuming drive cache: write through

SCSI device sda: 625142448 512-byte hdwr sectors (320073 MB)

sda: Write Protect is off

sda: Mode Sense: 53 00 00 08

sda: assuming drive cache: write through

 sda: sda1

sd 3:0:0:0: Attached scsi disk sda

sd 3:0:0:0: Attached scsi generic sg0 type 0

usb-storage: device scan complete

usb 1-3: USB disconnect, address 3

"fdisk -l" in Slackware also only shows one drive.

I booted from an Ubuntu 7.10 cd and it does see both drives (although it labels them sdc and sdd). Could I be missing a kernel module?

Thanks.

YOu may need to compile the option to 'scan all luns' into the kernel.

I'm pretty sure the kernel you're running has that available, so just make '/etc/rc.d/rc.scanluns' executable.

Quote:

Originally Posted by H_TeXMeX_H (Post 2947802)

I'm pretty sure the kernel you're running has that available, so just make '/etc/rc.d/rc.scanluns' executable.

Thanks H_TeXMeX_H, your suggestion worked perfectly! I just made rc.scanluns executable then ran it and I can now mount both drives.

Great, glad it works.

Quote:

Originally Posted by gnashley (Post 2947687)

YOu may need to compile the option to 'scan all luns' into the kernel.

Sorry to resurrect such an old thread, but I'm having the same problem with a Slackware.10.2 installation.

I can see the first disk but not the second of my USB enclosure.

I'm running Slackware-supplied(from 10.2) 2.6.13 kernel and following your suggestion I looked into the config for that kernel and found the following:

Code:

#

# Some SCSI devices (e.g. CD jukebox) support multiple LUNs

# 

# CONFIG_SCSI_MULTI_LUN is not set

# CONFIG_SCSI_CONSTANTS is not set

# CONFIG_SCSI_LOGGING is not set

I suppose that the config CONFIG_SCSI_MULTI_LUN setting is the one referred to in the "scan all luns" suggestion.

Given that for various reasons I am unable at the moment to recompile kernel, is there any other way to make the second disk drive visible to my machine?

I have connected the same USB enclosure in another machine running Slackware.12.2 and both drives were recognized and used with no problems.

Thanx for your time.

You need 'rescan-scsi-bus' which was included in slackware-11.0 in both the sysvinit and 'bin' packages. You can get the package for either one here:
ftp://ftp.slackware.at/slackware-11.0/slackware/a/
pr any other slackware mirror. Then use upgradepkg to upgrade your system to the new version. If you upgrade both of those, you should then be able to have rescan-scsi-bus run on each startup.

Or, you can simply run rescan-scsi-bus after startup or put it in a script somewhere so it gets when you need to access the drive. This separate utility (it's just a script) was later made unnecessary when slackware started compiling the scan-all-luns option into the kernel.