I am attempting to setup a BBB to boot via TFTP and mount a rootfs via NFS.
I am using Robert Nelson’s 2014-08-05 Debian lxde release image. I’ve examined the nfs-uEnv.txt in the boot partition and had a brief look at how the various environment variables interact with the default uboot setup. With the latest BBB uboot setup, it appears that TFTP boot and NFS rootfs functionality are now “packaged” together.
I’ve also read William Herman’s guides to setting up to boot via TFTP and mount the rootfs using NFS. Whilst helpful, these guides are now a bit dated (published June 2013) with respect to the latest uboot default setup.
I have setup a VirtualBox image running Linux Mint on my MAC. I have configured this image to be a NFS server and have arranged to export a rootfs (copied from a uSD card flashed with a disk image or created directly from RCN’s rootfs tarball). I have also configured TFTP on this image.
Where/how do I obtain a “zImage” to boot using TFTP? Is this simply the vmlinuz-xxx image in the /boot partition of the rootfs? (Running the “file” command on a vmlinuz image reports it to be a " Linux kernel ARM boot executable zImage (little-endian)".)
Unlike the normal so-called “uname” boot, the nfsboot setup does not appear to use an initrd ramfs image.
What function does this file system provide?
What impact, if any, does the lack of an initrd image have on a system booted via TFTP and running a rootfs via NFS?- In this new setup, what are the best practices for updating the kernel?
Given this setup, is it advisable to arrange to mount a user home directory via another NFS share to support development? Or would it be better to include the user home directory as part of a single (rootfs) NFS mount to keep things simple?
Thanks in advance!