I bought a Raspberry Pi and installed Raspbian and transmission. I want to connect my USB hard drive to save there the transmission's downloads. The HDD is formatted in FAT32, Windows recognizes it correctly. When I try to mount it in /dev/sda1 it prompts me:

mount: special device /dev/sda1 does not exists

fdisk finds only /dev/mmcblk0p1 and /dev/mmcblk0p2.

I also tried adding

/dev/sda1      /mnt/usb     vfat      uid=pi,gid=pi     0     0

to my /etc/fstab.

Can someone help me?

I tried mounting an NTFS-formatted USB flash drive and it mounts correctly.


3 Answers 3


Is the disk powering up? A USB HDD may require lots of current. I suggest you use a powered USB hub for the disk.

  • I tried with another HDD (FAT32) alimented, and it works fine. The fact is the don't-working HDD powers up when I turn on the Raspberry, but I'm not able to mount it. My 3.0 HDD, instead, doesn't even power up. In the afternoon I'm buying a powered USB hub then.
    – Federico
    Nov 3, 2013 at 12:34
  • Can you post the output of 'dmesg' and 'cat /var/log/syslog' ?
    – iceman
    Nov 5, 2013 at 14:42

Occasionally I get windows USB storage devices that do not have a "1st" partition and have to be mounted without the partition specifier so in fstab I have

/dev/sdc        /mnt/sdc    auto        user,noatime        0 1
/dev/sdc1       /mnt/sdc1   auto        user,noatime        0 1

and mount them with either

mount /mnt/sdc1


mount /mnt/sdc

if /dev/sdc1 does not exist.


Run sudo blkid and if you can't see your HDD that's mean it still not powered up. The Pi's USB ports only have output ~500mA as default so it might not enough for your HDD.

In this case you have to increase current output of those USB ports. Add max_usb_current=1 to /boot/config.txt then reboot the Pi :)

  • I advise against maxing the current to the USB ports, a powered USB hub is a much better option.
    – Darth Vader
    May 8, 2016 at 18:02
  • with this specific case : Raspbian + Transmission + one HDD. I cant see why it shouldn't. That HDD may draw more than 1.2A? Probably not :)
    – Aura
    May 8, 2016 at 18:47

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