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Cannot mount a USB key or disk device media to an ESXi/ESX host (1036340)


  • You cannot connect a USB key or disk device media to the ESXi/ESX host.
  • Connecting a USB key or disk device media to the ESXi/ESX host fails.

    Note: You may want to connect a USB key or a disk device media to the ESXi/ESX host to copy data to it from the host. For example, to gather the vm-support bundle from the host when the host has lost the network connectivity.

  • The USB key or disk device media appears under lsusb but does not mount correctly.
  • This issue occurs when the USB key or disk device media is formatted with a FAT16 partition and is of maximum size 2 GB.

    Note: ESXi does not support NTFS formatted devices.


This issue occurs because the usbarbitrator service has claimed the device to make it available for passthrough to virtual machines. You need to enable SSH / PuTTY for the host. For more information, see Using Tech Support Mode in ESXi 4.1 and ESXi 5.x (1017910).

For more information on formatting and preparing the USB drives above 2GB using VMFS, see:


To resolve this issue:
  1. Run this command to stop the usbarbitrator service:

    /etc/init.d/usbarbitrator stop

  2. Disconnect and reconnect the USB key or disk device media. The device is automatically mounted under /vmfs/volumes/NO NAME/.
  3. After using the device, start the usbarbitrator service by running this command:

    /etc/init.d/usbarbitrator start

Additional Information

For more information about USB device passthrough requirements and limitations, as well as steps to add a USB controller and a USB device, see USB support in ESXi/ESX 4.1 and ESXi 5.x (1022290).

See Also

Update History

10/14/2013 - Added ESXi 5.1 and 5.5 to Product Versions.

Request a Product Feature

To request a new product feature or to provide feedback on a VMware product, please visit the Request a Product Feature page.


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  • 87 Ratings