Debian buster and network configuration

[Gabriel Filion]

Hello,

I've decided to give my gnubee pc1 one more go. I was never able to make
it work using debian before but I saw that Neil Brown published some
linux 5.x images that could help.

I've installed the gnubee using the jessie install method, then upgraded
twice to have debian buster installed. And finally I flashed the
gnubee-5.10.1-gbpc1.bin image on it.

...and wow! now I can ssh in (this wasn't working with the 4.x images).


now since I had stopped configuring that machine in the middle of all of
the above, and I'm coming back to it now, I'm having some issues with
network configuration.

Currently, in the debian install the black eth port gets IP 192.168.1.1
and the blue one gets 192.168.2.2, both as static IPs -- I'd like to
change the IP for the blue port to some other address in the same subnet.

But /etc/network is mounted as a tmpfs and so if I change the interfaces
file in there, I lose the configuration change upon reboot.

If I boot the gnubee without any disk in it, I get a prompt on UART, but
no IP address has been assigned and no process is running.


.. I'm guessing that the IP might be configured in the flash somewhere
but I've been so far failing to change the address and I couldn't find
anything super useful in the wiki.

Is there an easy way to change the IP address that gets assigned?

[Gabriel Filion]

On 2021-07-30 4:37 p.m., Gabriel Filion wrote:
> Currently, in the debian install the black eth port gets IP 192.168.1.1
> and the blue one gets 192.168.2.2, both as static IPs -- I'd like to
> change the IP for the blue port to some other address in the same subnet.
>
> But /etc/network is mounted as a tmpfs and so if I change the interfaces
> file in there, I lose the configuration change upon reboot.
>
> If I boot the gnubee without any disk in it, I get a prompt on UART, but
> no IP address has been assigned and no process is running.

ah! well that email was me reaching a lowpoint.. but right after that an
idea popped up and I was successful in changing the network
configuration. It was on disk in the debian install

1. umount /etc/network -- to get rid of the tmpfs
2. modify the underlying hidden file "/etc/network/interfaces" that's
stored on disk
3. reboot and the change sticks around!


.. I don't quite understand why there's a tmpfs at all for the
/etc/network directory.
there's no entry about this in the fstab so it must be some boot script,
possibly in the linux 5.10.1 image that does that.. is there a good
reason for setting things up this way?