>
> *@William - Interesting.  Can you shed some additional light on this
> approach?  usbnet is Ethernet over USB, correct?  Is this just an
> alternative to using the wired Ethernet jack...and thus one still is
> mounting the rootfs via NFS from a NAS or something like that?  Or is this
> a different approach?  How does the BBB access/mount the rootfs?  Would
> this approach work for supporting cross development on a Linux laptop with
> a filesystem shared with the BBB?*
>

Yes, usbnet is the description modprobe gives the cdc_ether( g_ether?)
module on the host side I believe. I can think of two reasons why this is
useful.

First, if you're on a complex network for the host( university, work etc ),
this could alleviate some potential headaches. Secondly g_ether networking
is supposed to be nearly twice as fast when using Linux on both ends. This
means faster boots.

So far the initial testing I've done shows that it *is* faster by around
20Mbit / s using iperf as the test. This is from Windows 7 x64 as the host,
and a minimal Debian wheezy image on the BBB side( ~191M total ). Then
testing to my Debian support system, which is in a virtualbox VM on yet
another Windows 7x64 machine . . . is incredibly slow. Somewhere around
15Mbit / s. Which is terrible.

However, I was recently given an eeepc with a broken screen that I was able
to put back together ( came to me in pieces ), and get working again. I
have installed Debian wheezy on this machine, and will do some testing
between Linux<->Linux when i get the chance. Also I am likely to use one of
Robert's premade demo images, to show others how to do the same( in the
context of converting to NFS ). I am pretty sure this will be pretty easy,
but this is one reason why I want to try. TO make sure.


On Thu, Aug 14, 2014 at 11:32 AM, Robert Nelson <[email protected]>
wrote:

> On Thu, Aug 14, 2014 at 12:00 PM, Brian Anderson <[email protected]> wrote:
> > @Robert - Thanks for confirming!
> >
> > @William - Interesting.  Can you shed some additional light on this
> > approach?  usbnet is Ethernet over USB, correct?  Is this just an
> > alternative to using the wired Ethernet jack...and thus one still is
> > mounting the rootfs via NFS from a NAS or something like that?  Or is
> this a
> > different approach?  How does the BBB access/mount the rootfs?  Would
> this
> > approach work for supporting cross development on a Linux laptop with a
> > filesystem shared with the BBB?
> >
> > I was able to download a kernel via TFTP, boot and successfully mount an
> NFS
> > rootfs...sorta.
> >
> > I had originally setup a rootfs on the NFS share as follows:
> >
> > Setup a uSD card:
> >
> > Created using
> >
> https://rcn-ee.net/deb/testing/2014-08-05/lxde/bone-debian-7.6-lxde-armhf-2014-08-05-4gb.img.xz
> > Configured and setup on a BBB Rev C.
> > Successfully booted, run, and updated numerous times on the BBB.
> >
> > Shutdown the BBB, move the uSD card to my MAC.  Then, from Linux Mint
> > running in Virtual Box on the MAC:
> >
> > Mount the uSD card.
> > Create a tarball from the mounted uSD card whilst sudo.
> > Untar the tarball into the exported NFS share location on Linux Mint
> whilst
> > sudo.
> >
> > My assumption was that I should be able to move/copy the rootfs from the
> uSD
> > card using a separate system.  Note that the uSD card was NOT running a
> live
> > system when I made the copies.
> >
> > Unfortunately, when the BBB subsequently tries to boot using the copied
> > rootfs, the following happens:
> >
> > [....] Checking root file system...fsck from util-linux 2.20.1
> > fsck.ext4: No such device or address while trying to open /run/rootdev
> > Possibly non-existent or swap device?
> > fsck died with exit status 8
>
> When you copied the rootfs, the root device is listed in /etc/fstab,
> along with the fsck call. Just minimze it:
>
> voodoo@hades:$ cat /opt/wheezy/etc/fstab
> debugfs  /sys/kernel/debug  debugfs  defaults  0  0
>
> > So, I resorted to creating a fresh rootfs using
> >
> https://rcn-ee.net/deb/testing/2014-08-05/lxde/debian-7.6-lxde-armhf-2014-08-05.tar.xz
> .
> >
> > All went fine and the system booted and I could ssh to it.
> >
> > Unfortunately, this system seems to have some broken network setup.  A
> bit
> > of digging reveals that /etc/resolv.conf is not setup correctly:
> >
> > domain localdomain
> > search localdomain
> > nameserver 192.168.1.1
> >
> > Whilst /etc/resolv.conf from the rootfs on the original uSD card that
> I've
> > been using:
> >
> > domain hsd1.wa.comcast.net.
> > search hsd1.wa.comcast.net.
> > nameserver 10.0.1.1
>
> /etc/resolv.conf is autogenerated on bootup...
>
> > Also, /etc/network/interfaces does not have the stanzas for the USB
> gadget,
> > and /etc/udhcpd.conf is not setup properly.  There may be other issues,
> but
> > this is as far as I've looked.
>
> odd..
>
>
> Btw, here's how i setup the nfs rootfs.. I first boot the bbb, with
> the microSD, then run this:
>
>
> https://github.com/RobertCNelson/boot-scripts/blob/master/tools/developers/nfs-rsync.sh
>
> Just change all occurances of:
>
> 192.168.0.10 & /opt/wheezy/
>
> and it should work for you.
>
> I should make it more generic, for people other the me to use..
>
> Regards,
>
> --
> Robert Nelson
> http://www.rcn-ee.com/
>
> --
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