Ubuntu 18.04: Cannot mount Micro SD DC I Class 10

Recently we tried to mount a Micro SD card that was formatted using the exFat format. To do so we used the build in card reader of a laptop that was running Ubuntu 18.04. To our disappointment, the OS was able to “see” the device as ‘/dev/mmcblk0’ but it could not automatically mount it.

First step we did was of course to update the system using:

sudo apt update;

and then we made sure we had all the necessary packages installed:

sudo apt-get install exfat-fuse exfat-utils;

Unfortunately, we still could not automatically mount the device. So we decided to try and mount it manually which also failed:

sudo mount -t exfat /dev/mmcblk0 /mnt/vmfs;
FUSE exfat 1.2.8
ERROR: failed to read boot sector.

As we were not sure what was wrong we decided to do an experiment which turned out to be our solution: to use an external card reader and try again.. guess what? It worked!!

We will investigate further the issue with the build in card reader but for now we are able to work around the issue with the external card reader.


Fedora 23: Support exfat

The Background:

Recently we got our hands on a GoPro Hero4 Black camera and we used a 64GB memory card as storage. The file system on the card is exFAT (Extended File Allocation Table), which is a Microsoft file system designed for flash drives. It is proprietary and Microsoft owns patents on several elements of its design. exFAT has been adopted by the SD Card Association as the default file system for SDXC cards larger than 32GiB.

The issue:

Fedora does not support exFat due to the licensing issues that Microsoft applied to the product and thus we could not mount the card on our machine.

The solution:

We installed the fuse-exfat driver from rpmfusion.org using the following commands.

#Enable access to both the free and the nonfree repository
#free repository: for Open Source Software (as defined by the Fedora Licensing Guidelines) which the Fedora project cannot ship due to other reasons
#nonfree repository: for redistributable software that is not Open Source Software (as defined by the Fedora Licensing Guidelines); this includes software with publicly available source-code that has "no commercial use"-like restrictions 
su -c 'dnf install http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm';

#Perform the installation
sudo dnf install fuse-exfat;

More background:

RPM Fusion provides software that the Fedora Project or Red Hat doesn’t want to ship. That software is provided as precompiled RPMs for all current Fedora versions and Red Hat Enterprise Linux 5 and 6.