Kernel images
There are two kernel images in the binaries/kernel directory.
- zImageBoot is the standard one, which will mount a root filesystem from flash.
- zImageInitrd uses an initial RAM disk for its root filesystem.
Root password
The default root password is 'rootme'. You'll be asked to change it at first login. I changed it to something else and then immediately back to 'rootme' so it remains the same as the Balloon 2 default root password.
File transfer
To use ZMODEM to send files to the Balloon while it's running Linux, lrzsz needs to be installed. The Debian package file for this is conveniently in /root, so after logging in:
dpkg -i lrzsz_0.12.21-4.1_arm.deb
will do the necessary.
Kernel modules
The root filesystem image doesn't have any kernel modules installed as standard, so you'll have to upload them to the Balloon. There's a file modules.tgz in the directory binaries/kernel. Upload this file and untar it into /lib/modules.
cd /lib/modules tar xzf [wherever]/modules.tgz
I did
depmod -a
afterwards because it seemed like a good idea, but I don't know whether it's really required.