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[EX/QFX] Unable to mount USB drive on EX switches



Article ID: KB30988 KB Last Updated: 22 Oct 2020Version: 3.0

This article describes an error message generated while attempting to mount a USB device on EX switches. Two workarounds are suggested.


While mounting a USB drive on an EX switch device, the following error message may be observed:

root@% mount_msdosfs /dev/da0s1 /mnt 

mount_msdosfs: /dev/da0: Invalid argument


 This error might be caused by problems with the USB drive such as an unsupported format (exFAT).


Suggested workarounds:

  • Use another USB drive with FAT16 or FAT32 format. 
  • Newer USB 3.0 drives with large capacity use the exFAT format, and might not support the FAT32 format. Try using USB 2.0 drives with smaller capacity. 

Modification History:
2020-10-20: Article reviewed for accuracy; no changes required.

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