USB HD problems

[kmc77]

Newbie question. I've recently installed Mandrake 9.2 and am having a little problem with my USB HD. Linux recognizes the drive at startup and mounts it, but occasionaly after restarting the comp., it will mount another copy under "removeable2" then "removeable3" and so on. if I try to unmount, nothing happens.

 

Any one have any helpfull tips. Also, is there a way to keep this from happening?

[DragonMage]

It's a "feature" of supermount and mandrake autodetection. It will automatically detect the harddrive (or any other usb storage device even) and create a directory and mount it via supermount. If you want that usb harddrive as a "semi permanent" storage device, you can use the mandrake control center, then go to mount point and diskdrake. There should be a folder named sda beside your hard drive folder. You can then toggle expert mode, select that folder, select the partition and uncheck supermount. After that you can mount it manually.

 

Anyway, that 's the gui way to solve your problem. There is another way that requires editing your /etc/fstab file, but since I don't have a usb storage device, I am not sure how to edit the file.

[arthur]

I don't think it's necessary to disable supermount...

just add to /etc/fstab: (login as root, just doubleclick the file)

 

/dev/sda /mnt/removable vfat
user,iocharset=8859-1,codepage=850,noauto,suid,umask=0 0 0

 

If your drive shows up as sda1 or whatever, modify appropriately. I'm not sure about the codepage=850 part could anyone offer some info about it?

 

Then if you want to mount the drive(as a normal user) just go to the terminal and type

 

mount /dev/sda

 

To unmount:

 

umount /dev/sda

 

Note it's umount, not unmount. To automate it just make a script, but it's so easy to type I don't bother.

Edited February 8, 2004 by arthur

[kmc77]

thanks for the suggestions. I'll try them when I get back to my Linux machine.

[arthur]

ahhh! bad advice!

 

it's not iocharset=8859-1, it's iocharset=iso8859-1. sorry i'm still a newbie i think...here's the correct code, put all in one line.

 

/dev/sda /mnt/usbdrive vfat user,iocharset=iso8859-1,codepage=850,noauto,suid,umask=0 0 0

 

and you should login as root, make a folder in /mnt/ named usbdrive or something, it's up to you to name it. Right-click the folder and under the permissions tab check all the write permissions and the group to 'users'. Then login as normal user and see if it mounts, you should see an icon on the desktop.

[aRTee]

Also make sure that there is no line in /etc/fstab that starts with

"none" and has a reference to /dev/sda in it.

 

BTW! arthur, I think it should be

/dev/sda1

and not

/dev/sda

 

Quoting my own website:

in my /etc/fstab:

/dev/scsi/host1/bus0/target0/lun0/part1 /mnt/hd-sda1 vfat rw,noauto,user,exec 0 0

which I put instead of what Mandrake automatically created:

none /mnt/hd supermount dev=/dev/sda1,fs=ext2:vfat,--,codepage=850,kudzu,iocharset=iso8859-15 0 0

and like this, I can mount the drive as a user with:

mount /mnt/hd-sda1

and all works fine.

 

note that I had done

mkdir /mnt/hd-sda1

as root before, and that you can substitute that name with anything you like.

 

Also, you can create 2 desktop/taskbar icons with the commands behind it:

mount /mnt/hd-sda1

and

umount /mnt/hd-sda1

 

Edit:

note that for /dev/sda1 I use the full path: /dev/scsi/host1/bus0/target0/lun0/part1; check with

ll /dev/sda1

where it points, or just use /dev/sda1

Edited February 9, 2004 by aRTee

[arthur]

mine is /dev/sda, not sda1. I don't know why, but works for me. It's the peculiar american way of counting starting from zero.

[aRTee]

Strange.

 

Like with ide harddrives, the device is the whole drive:

/dev/hda

/dev/hdb

 

and the counted version is the partition:

/dev/hda1

/dev/hda5

etc.

 

This is the same for scsi harddrives, and usb drives are emulated through the scsi layer.

/dev/sda

then is the whole drive/device, and

/dev/sda1

/dev/sda2

are partitions on that drive.

 

But anyway, like I said, they are usually links anyway.

Just do

ll /dev/sda

and you'll see.

 

BTW it's not american to start counting from zero, it's (well used to be) standard digital hardware engineering practice...

[arthur]

as an engineering student most of what I see is recognizably american...

 

the only country still using imperial units for engineering, talk about shooting yourself in the metre... :D

[Gowator]

This is a 'feature' of FAT12.

Mainly you see this on memory sticks or compact flash,

 

as aRTee explains above

/dev/sda isthe whole drive and sda1.... the first partition etc.

However FAT12 doesn't support partitions... (I think)

therefore the whole drive is a single default partition.

 

Think of it lik containers

sda is the big container....

inside you can have other smaller boxes sda1 sda2 etc.

Theese are primary partitions. They can be any size from the size of the sda box to very small.

These boxes can hold other boxes.... (xda1-4 are PRIMARY PARTITIONS)

the samller boxes they can hold are called SECONDARY partitions xda5-9

 

However this is only really valid for a 'real disk' not a Cd or compact flash. (you mount /dev/hdc if a CD is secondary master not hdc1)

/dev/cdrom is usually just a link to this....

 

Sometimes it has a fake partition for compatibility... then it will be sda1

 

 

FREE INFORMATION:D

Counting from zero is not American its Arabic.

The greeks and romans had no zero.

The bible has no year zero, it goes from 1BC to 1AD.

 

This gave the romans a certain disadvantage when dealing with complex numbers.... the smallest number they had was 1/infinity

 

The reason computers count from zero is really very simple....

Computers work in bits and logically the first bit is everything empty

00000000 (on a 8 bit system)

the second is

00000001 =1 and the third 00000010 =2

 

erm, thats all there is to it except that if it didn't programming would be a lot harder. How do you change a <<a>> to a <<A>>

very simple you just move the bits down one or up one in the other direction.

 

Look at a chmod statement, well only look at three significant bits instead of owner,group, world. (drwxrwxrwx)

 

Each bit represents a unique combination for Read, Write, Execute.

How do you represent this in binary

If we want execure only we set the rightmost bit.... ie we want 001 therefore in decimal that's 1. What if we want to read and execute but not write... thats 101 = 5 ... and if we want everything thats 111=7

Each combination is UNIQUE.

3=011 = write,execute

Now

Where would we be if we had no zero ?????

I wouldn't be able to say I don't want a certain attribute....

We would need a whole extra bit to describe the same thing....

[arthur]

well those people who say Arabs have contributed nothing to civilization couldn't be more wrong. :)

[Gowator]

MORE TRIVIAL information..... (pointless but what the hell)

 

Well, amongst other things a heck of a lot of medicine, geometry and astronomy.

Bhaddad wasn't called the cradel of civilisation for nothing.

 

Erm, they also sacked Alexander library and burned the books for being heretical.

 

Its a somewhat mixed bag....

perhaps the most bizarre is after inventing the arabic numbering system we use today, base 10 instead of the Roman Base V they then reverted back to the hindi/sanskrit numbers which suffer the disadavange of not actually being very readable. In particular telling the difference between a 2 and 3 is not easy when its hand written...

[arthur]

This post might get this thread moved, but...

 

Arabs preserved important Greek books while europeans were bashing the brains out of each other in the dark ages. The crusades unfortunately turned them overprotective of religion, and mr. bush is only following 800-year old foreign policy.

 

Anyway, back to the topic, a USB HD would have FAT32 rather than FAT12, so I guess sda1 would be applicable. My brandless, made-in-china USB key uses the floppy format, *surprise* it has "Linux kernel 2.4 compatible" on the box. Not bad for a cheap key.