External usb hard drive warning message
 

I recently bought a new usb external hard drive so I can back up my data and have some extra storage, and I'm trying to get it partitioned and formatted so I can start using it. I turned it on, plugged it in, and took a look at /var/log/messages. The last lines are the following:

That line about "data integrity not assured" doesn't look very good. Why is that there, and what do I need to do to fix it?

Also, I read that the line about not being claimed by a driver means I need to enable usb support in my kernel or something like that, but lsmod lists

usb-storage 33296 0 (unused)

among its entries. Do I need a specific module for this type of drive or something?

The line “WARNING: USB Mass Storage data integrity not assured” is simply stating that if you pull the plug on the drive without unmounting it, you could lose your data. This is important as Linux will cache data before writing to the disk. If you yank it without unmounting it, you could have data that has not been written yet.

Ah ok, makes sense. The only thing worrying me now is that line about not being claimed by an active driver. A bit of searching seemed to show that shouldn't be there, but I can't find any information on how to resolve that. A few people on various reviews of the drive say it works under Linux, and I seem to have all the appropriate kernel modules, so I don't know what else to do.

Any suggestions at all? The dmesg output says the drive isn't claimed by an active driver, and that doesn't sound good for something I'll be using to backup all my data. Googling suggests the same. Can anyone else with experience mounting usb devices pass on some advice?

i havent been able to find an exact cause but from what im finding, that message is as benign as the first one you asked about.

I have a couple of external USB devices I use, my Archos Jukebox MP3 player and an external USB enclosure for an old laptop drive.

If you do a clean boot of your system, do an "ls /dev/sd*". Make a note of what you find. Plug in your USB device, and wait a minute. Then, do another ls, and you should see a new /dev/sd<something> device. On my system, I get a /dev/sda (possibly a /dev/sdb, if I've got both plugged in).

After you find the device, you should be able to fdisk it, make a file system, and mount it.

I'm using SuSE currently, and that's where my USB disks show up. It may be different on yours, but it's a place to start.

Does the drive function correctly? Have you tried writing something to it, unmounting, unplugging, plugging back in, remounting, and making sure it is still there?

If the driver works, I wouldn't worry about it.

I agree, but i did find out a bit more info about that. What it means is it is properly connected and USB stack had no problems talking to the device. However none of currently loaded drivers recognized this device. If you know the module that you need try to modprobe it in.
Also if you add sync to the mount options it will write all the info to the disk synchonosly to the chache, or you can just type sync to sync it up, umount automaticly does that too.

TB0ne: Thanks for the advice, but finding where it is assigned isn't the problem at this point. The message tells me which sd device it is, so I could go ahead and start playing with it, but I just want to address the driver message before I do that.

Others:
If this was an mp3 player or a camera or almost anything else, I would go ahead and start using it and assume no errors or issues means there are no problems. This will hold backups of my whole system, though, and when I'm dealing with critical data I don't want to be using the "it works, so nothing must be wrong" principle. If I'm getting a message that I'm missing something, I'd kind of like to address that first.

As far as I can tell, I have all the proper USB modules loaded, unless there's some specific one for Western Digital external drives I don't know about.

What's the difference between the system being able to successfully communicate with and recognize the device, and having the proper driver? If the default usb modules can do everything that needs to be done, why would there even be a need for specific drivers? It seems like if there are specific drivers, there must be some reason why it would be a good idea to have them.

Thanks for letting me know about sync. Is that not the default for mount? It sounds like it would be a good idea just in case the cord got accidentally pulled or something, but I think I'm satisfied with it just syncing when I umount too.

Any more information on why exactly you'd want a specific driver rather than whatever the generic setup is or on how to find one for this drive would be greatly appreciated.

You should'nt need any specific driver. Have you even tried using it yet? Does it mount ok? Read/Write ok? I really don't know why it thinks it needs a specific driver, nor have i been able to find any information regarding this behavior as detrimental to the devices operation; specificaly with external storage devices as most of them are rather standardized in the way they I/O data.

Oh, and no that is not mounts default behavior with external storage devices to minimize bus traffic i think.

Ok. I started looking at information online about the usb-storage module, and I realize now that that's the generic driver provided for the vast amount of cases where a specific driver isn't available. I didn't understand that that message was saying "we can't find a specific driver for this device, so we'll default and use usb-storage instead." It looks like at least a few external Western Digital drives run fine on usb-storage, so I'm confident enough now to start playing with it. I'll be back with more questions if anything goes wrong. Thanks again all for your help.