Solved! Mounting a microSD card on newly updated Omega2+

Seth Hall

I just upgraded my Omega2+ to v0.1.9 b149 and I can now see my SD card as mmc0:

Mon Jan 16 19:41:54 2017 kern.info kernel: [ 4.731010] mmc0: new high speed SDHC card at address 0007
Mon Jan 16 19:41:54 2017 kern.info kernel: [ 4.822031] mmcblk0: mmc0:0007 SD32G 29.0 GiB
Mon Jan 16 19:41:54 2017 kern.info kernel: [ 4.915117] mmcblk0: p1 p2 p3

Now, how do I mount this device, and especially, as an expansion/overlay for the root partition?

 Thanks,
                Seth

Solved!

Jan 23: After reformatting my 32Gb microSD card, I was able to mount it successfully as /mnt/sda1. The sequence of instructions I followed is below.

Note that my SD card had been formatted for a bootable Fedora test installation previously, which left me with several unneeded and unwanted partitions, e.g.,

Mon Jan 16 19:41:54 2017 kern.info kernel: [ 4.915117] mmcblk0: p1 p2 p3

I reformatted the /dev/mccblk0 device, which removed these unwanted partitions and left me with the "0" partition, e.g., the whole device, as follows:

mkfs.ext4 /dev/mmcblk0

then mounted the new 32Gb partition thus:

mkdir /mnt/sda0
mount /dev/mmcblk0 /mnt/sda0

yielding this:

root@Omega-7117:/etc# df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/root 5632 5632 0 100% /rom
tmpfs 62880 200 62680 0% /tmp
/dev/mtdblock6 25728 13856 11872 54% /overlay
overlayfs:/overlay 25728 13856 11872 54% /
tmpfs 512 0 512 0% /dev
/dev/mmcblk0 29767652 45080 28187392 0% /mnt/sda0

Life is good! Now I'll try to create an overlay so that I'll have plenty of space on the 'root' device for a development environment. I'll post back when I've succeeded.

Later Jan 23:

Following up on using my microSD to expand the root file system, I used the "exroot with pivot-root" technique described here:

  https://wiki.onion.io/Tutorials/Using-USB-Storage-as-Rootfs

but with appropriate references to my new SD device, and it worked perfectly. I now have a ~30gb root partition to work with, and this partition will be updated with all firmware updates I may chose to apply in the future. Nice. Here is what my file systems look like now:

root@Omega-7117:/# df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/root 5632 5632 0 100% /rom
tmpfs 62880 268 62612 0% /tmp
/dev/mmcblk0 29767652 102380 28130092 0% /
tmpfs 512 0 512 0% /dev
/dev/mmcblk0 29767652 102380 28130092 0% /tmp/run/mountd/mmcblk0

Hope this helps.

Brad Buskey

https://wiki.onion.io/Tutorials/Contents#storage-space

Kit Bishop

@Brad-Buskey As per my recent response to a separate post of yours:

The link you give is really nothing to do with the SD card, rather it deals with using a USB drive to extend your disk space and/or virtual RAM space.
There isn't really much info about using the SD card yet - hopefully it will be forthcoming soon - hint, hint to the Omega devs

That said, I suspect that the link will be applicable to SD card as well as USB drive, however one should probably take note of: https://community.onion.io/topic/1295/more-system-disk-space-using-pivot-overlay-and-pivot-root-on-the-omega2

Brad Buskey

As I said, I was able to use that link and get my SD card working the same as you would a USB.

Seth Hall

@Brad-Buskey Brad, what device (device name), did you use to mount your SD card? Can you provide an example of how you mounted your SD card? Thanks.

Brad Buskey

@Seth-Hall The following is what I did on both of my devices, and it worked both times.

opkg update
opkg install kmod-usb-storage-extras e2fsprogs kmod-fs-ext4
mkfs.ext4 /dev/mmcblk0p1
mkdir /mnt/sdcard
mount /dev/mmcblk0p1 /mnt/sdcard