USB HDD Mounting Question
 

I have a WD 82.6GB internal HDD installed in an external USB2.0 drive bay connected to my computer. Previously, I assume through SCSI emulation, it was considered /dev/sda. Now, for some reason, it's not mounting properly. I have the following command in my /etc/rc.local

mount /dev/sda1 /backup

Now this mount is no longer working. I assume that the device has changed. I grabbed the following out of /var/log/messages:

Jan 29 20:35:27 localhost kernel: usb.c: USB disconnect on device 2
Jan 29 20:35:55 localhost kernel: hub.c: USB new device connect on bus4/1, assigned device number 3
Jan 29 20:35:55 localhost kernel: usb.c: USB device 3 (vend/prod 0xc0b/0xb001) is not claimed by any active driver.
Jan 29 20:35:58 localhost /etc/hotplug/usb.agent: Setup usb-storage for USB product c0b/b001/1110
Jan 29 20:35:58 localhost kernel: Initializing USB Mass Storage driver...
Jan 29 20:35:58 localhost kernel: usb.c: registered new driver usb-storage
Jan 29 20:35:58 localhost kernel: scsi1 : SCSI emulation for USB Mass Storage devices

I'm pretty sure that this excerpt from the log is after I realized that the drive wasn't mounted and unplugged the drive and turned it off and plugged it back in and turned it on.


Now that you have the background info, my question is this: How do I determine what device the drive is? I found it before on a wild guess. :confused:

I have a USB smartdrive that i mounted with linux basically the same way you did with a hard drive.

mount /dev/sda1 /mnt/usb

that's basically what i did, maybe the fault was in your choice of sda over sda1?

have you added ANY other block devices such as HDDs CDs CDRs CDRWs DVDs Zips LS-120s etc?

if any of these use scsi emulation, like your USB drive does they can "bump" the drive out of sda and make it sdb or sdc.

Who was that in referance to? hehe

Uhh that is why i have the usb ( since it is temporary like a florry disk) as sda1.

I didn't add anything at all. It was working, I rebooted my machine, and then it wasn't working. Given that little excerpt from my log, I'd say that it's definitely being recognized and it's plugged in correctly and such. The only other USB device is my mouse, so those lines must be in reference to the USB HDD.

I tried mounting /dev/sdb1 (it only has one partition, so I know that at least the number is right), but that didn't work either.

I thought that maybe there was some utility or log file I could consult to find out what scsi device it was being emulated as. :confused:

Another touch of information I've found while snooping around - Here is what I *used* to get in my /var/log/messages when booting when the USB HDD worked correctly:

Jan 26 01:45:05 localhost kernel: Attached scsi disk sda at scsi0, channel 0, id 0, lun 0
Jan 26 01:45:05 localhost kernel: SCSI device sda: 160836480 512-byte hdwr sectors (82348 MB)
Jan 26 01:45:05 localhost kernel: sda: sda1
Jan 26 01:45:05 localhost kernel: EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended


Now I get:

Jan 29 20:35:55 localhost kernel: hub.c: USB new device connect on bus4/1, assigned device number 3
Jan 29 20:35:55 localhost kernel: usb.c: USB device 3 (vend/prod 0xc0b/0xb001) is not claimed by any active driver.
Jan 29 20:35:58 localhost /etc/hotplug/usb.agent: Setup usb-storage for USB product c0b/b001/1110
Jan 29 20:35:58 localhost kernel: Initializing USB Mass Storage driver...
Jan 29 20:35:58 localhost kernel: usb.c: registered new driver usb-storage
Jan 29 20:35:58 localhost kernel: scsi1 : SCSI emulation for USB Mass Storage devices


Please help! I'm stumped!! :confused:

have u unplugged the usb in between this problems?