"Fixing" problem USBs

[manyroads]

[...]
With running sgdisk and wipfs you have the chance twice to wipe your system.
So I would not really recommend those "dangerous" commands to "newbies" nor to "oldies", as with one wrong pressed key your system might be wiped.

But it is only after you delete an entire drive full of data that you truly understand the value of a backup.

[Head_on_a_Stick]

To backup a partition table use

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sgdisk --backup=sdX_table.bak /dev/sdX

To restore the table:

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sgdisk --load-backup=sdX_table.bak /dev/sdX

To make a backup while wiping the filesystem signatures use

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wipefs --all --backup /dev/sdX

To restore the signatures:

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dd if=$backup_file of=/dev/sdX seek=$((OFFSET)) bs=1 conv=notrunc

Replace $backup_file with the name of the backup file, which will be called wipefs-sdX-OFFSET.bak, use the OFFSET number in the seek option.

[manyroads]

[...]

Thank you @Head_on_a_Stick. I have added all of your latest suggestions.

[oops]

... Too many roads to "Fixing" problem USBs ;-)

Here I used "udiskie -nt" with success for some issues with some usb keys.

[manyroads]

... Too many roads to "Fixing" problem USBs ;-)

Here I used "udiskie -nt" with success for some issues with some usb keys.

Thank you! I have added your contribution.

[oops]

Your are welcome manyroads ... the idea was from handy:
viewtopic.php?p=500514#p500514

[Head_on_a_Stick]

And partition-clear shall actually exactly do what the other two tools supposed to do. In addition partition-clear gives you a kind of safety measure for you system,
as it will only provide you found USB device to select from.
With running sgdisk and wipfs you have the chance twice to wipe your system.
So I would not really recommend those "dangerous" commands to "newbies" nor to "oldies", as with one wrong pressed key your system might be wiped.

Well I don't really agree that the live-usb-maker tool is necessarily any safer than the simple commands I listed because the all it does it list any connected drives that have "1" in /sys/block/sdX/removable and this would include any USB-attached drives.

Here's an example to illustrate why your tool can be dangerous:

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demo@mx1:~
$ sudo live-usb-maker partition-clear
Creating new config file /root/.config/live-usb-maker/live-usb-maker.conf
===============================================================================
Starting live-usb-maker
===============================================================================
The live media is not mounted
                                                                                                  
Please select the target usb device                                                               
  > sdb       3.8G Generic Flash Disk                                                             
  > sdc     931.5G TOSHIBA MK1059GSM                                                              
Press <Enter> to select the highlighted entry                                                     
Use 'h' for help, 'r' to redraw, 'q' to quit

In this case /dev/sdc is my backup drive and your tool is offering to wipe it for me

Not "safe" at all...

I would recommend that people use their brains rather than rely on a third-party tool that may offer false reassurances.

To make sure the correct device is used for my suggested commands first run this command in a terminal:

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dmesg -w

^ That will print out the kernel ring buffer messages and any new messages will be added to the bottom of the screen.

Now plug in the problematic USB stick and wait for the new messages, for example:

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demo@mx1:~
$ dmesg -w
[list of old kernel messages]
[ 1197.183867] usb 1-4: new high-speed USB device number 5 using xhci_hcd
[ 1197.315852] usb 1-4: New USB device found, idVendor=0951, idProduct=1665, bcdDevice= 1.00
[ 1197.315856] usb 1-4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1197.315858] usb 1-4: Product: DataTraveler 2.0
[ 1197.315860] usb 1-4: Manufacturer: Kingston
[ 1197.315862] usb 1-4: SerialNumber: 60A44C413E29FE61EB4CF82B
[ 1197.316592] usb-storage 1-4:1.0: USB Mass Storage device detected
[ 1197.317441] scsi host3: usb-storage 1-4:1.0
[ 1198.396398] scsi 3:0:0:0: Direct-Access     Kingston DataTraveler 2.0 1.00 PQ: 0 ANSI: 4
[ 1198.397247] sd 3:0:0:0: Attached scsi generic sg3 type 0
[ 1198.397515] sd 3:0:0:0: [sdd] 15131636 512-byte logical blocks: (7.75 GB/7.21 GiB)
[ 1198.397784] sd 3:0:0:0: [sdd] Write Protect is off
[ 1198.397786] sd 3:0:0:0: [sdd] Mode Sense: 45 00 00 00
[ 1198.398033] sd 3:0:0:0: [sdd] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 1198.405287] sd 3:0:0:0: [sdd] Attached SCSI removable disk

^ So we can see that a new (removable) drive has been added, a Kingston DataTraveler USB 2.0 device and this has been assigned to /dev/sdd so that is what we should use in the sgdisk & wipefs commands.

Even newbies & oldies should be able to follow this method without risk of being confused

[fehlix]

Not "safe" at all...

Yes, you can clear your usb-backup drive, if you want

[sunrat]

I would recommend that people use their brains rather than rely on a third-party tool that may offer false reassurances.

If people used their brains the forums would be really quiet!

[manyroads]

I would recommend that people use their brains rather than rely on a third-party tool that may offer false reassurances.

If people used their brains the forums would be really quiet!

+8 :lipsrsealed: