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[NFX] How to re-use a USB stick after using it for USB install to upgrade software



Article ID: KB33439 KB Last Updated: 14 Feb 2020Version: 2.0

This article explains why a USB stick does not work for normal use in your PC after using it for USB install. It also provides instructions on how to reformat the USB stick so that it can be used again.



After using a USB stick for USB install to upgrade software on NFX, the same USB stick cannot be used again on a PC.

When reading from a Windows machine, it will give you an error stating that the volume needs to be formatted.



This is due to limitations with partitioning on the USB.



Once you make a USB stick bootable, attempts to format it on your PC will fail. In order to revert this USB to a state where you can use it on your PC, or for other purposes, leave the USB stick in the USB slot on the NFX, then within hypervisor, use the following:

root@local-node:/dev# dd if=/dev/zero of=/dev/sdb bs=1024k
dd: error writing '/dev/sdb': No space left on device
14809+0 records in
14808+0 records out
15527313408 bytes (16 GB) copied, 1970.14 s, 7.9 MB/s

This will revert the USB to normal, and you can format it on your PC as usual.

You can alternatively format the USB in the PC instead (to alleviate resources being used on the NFX150 device). To do this, on Windows, select Start > Run > command, and enter Diskpart.

Accept permissions to run this program. Then follow the procedure below:

Microsoft DiskPart version 10.0.16299.15
Copyright (C) Microsoft Corporation.
On computer: testing-T450

DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  ---  ---
  Disk 0    Online          465 GB      0 B        *
  Disk 1    Online           14 GB    12 GB        *    <=-- USB stick

DISKPART> select Disk 1

Disk 1 is now the selected disk.


DiskPart succeeded in cleaning the disk.

DISKPART> create partition primary

DiskPart succeeded in creating the specified partition.

DISKPART> select partition 1

Partition 1 is now the selected partition.

DISKPART> format fs=ntfs quick

  100 percent completed

DiskPart successfully formatted the volume.

DISKPART> assign

DiskPart successfully assigned the drive letter or mount point.


At this point, you can re-use your USB stick on your PC.


Modification History:

2020-02-14: Added symptom seen when mounting USB on Windows


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