2004-10-11-2120Z


How's this for a minimal nfsroot system:

I have no name!@box:/# du -b -s
5070848 .
I have no name!@box:/# echo $(find /) | fold -s
/ /bin /bin/bash /bin/dd /bin/mount /bin/cp /bin/ldd /bin/cat /bin/ls /bin/ps /bin/top /bin/strace /bin/ln /bin/chown /bin/mkdir /bin/more /bin/less /bin/lynx /bin/ping /bin/cut /bin/find /bin/fold /bin/du /boot /dev /dev/console /dev/null /dev/ram0 /dev/ram1 /dev/ram2 /dev/zero /dev/ram3 /dev/ram4 /dev/pts /lib /lib/libncurses.so.5 /lib/libdl.so.2 /lib/libc.so.6 /lib/ld-linux.so.2 /lib/libext2fs.so.2 /lib/libcom_err.so.2 /lib/libblkid.so.1 /lib/libuuid.so.1 /lib/libe2p.so.2 /lib/librt.so.1 /lib/libpthread.so.0 /lib/libproc.so.3.2.1 /lib/libz.so.1 /lib/libnss_files.so.2 /lib/libnss_nis.so.2 /lib/libnss_dns.so.2 /lib/libnss_compat.so.2 /lib/libresolv.so.2 /lib/libpopt.so.0 /opt /root /root/.bash_history /sbin /sbin/mke2fs /sbin/route /sbin/pump /sbin/ifconfig /sys /usr /usr/share /usr/share/terminfo /usr/share/terminfo/l /usr/share/terminfo/l/linux /usr/share/terminfo/x /usr/share/terminfo/x/xterm /usr/share/terminfo/r /usr/share/terminfo/r/rxvt /usr/share/terminfo/v /usr/share/terminfo/v/vt100 /home /mnt /proc /tmp /var /ref /ref/etc /ref/etc/init /ref/etc/lynx.cfg /ref/etc/protocols /ref/etc/services /ref/var /ref/home /ref/home/user /etc /etc/init /etc/services /etc/lynx.cfg /etc/protocols
I have no name!@box:/#

Don't sweat the "I have no name!" stuff, that's just because I was chrooted into the nfsroot system on the bootserver itself; you don't see that on the target boxen. So far they can only lynx around on the net, but that's a start! And I'm learning a lot building it bottom-up this way. Here's /etc/init:

#!/bin/bash
exec </dev/console >/dev/console 2>/dev/console
PATH=/bin:/sbin
ramfs() {
 dd if=/dev/zero of=/dev/ram$1 bs=1024 count=4096 &>/dev/null
 mke2fs -q /dev/ram$1 &>/dev/null
 mount -n /dev/ram$1 $2 &>/dev/null
}
echo Setting up ramdisks...
ramfs 0 /tmp
ramfs 1 /etc
ramfs 2 /var
ramfs 3 /home
mount -n -t proc proc /proc &>/dev/null
cp /proc/mounts /etc/mtab
# make sure ref has hardlinks to all necessary files
cp -a /ref/* /
mount -o rw,gid=5,mode=620 -t devpts devpts /dev/pts
# the following only works while host knows only its IP
netroot=$(echo $HOSTNAME | cut -d '.' -f 1,2,3)
cp /proc/net/pnp /etc/resolv.conf
route add default gw $netroot.1
echo Well, here you go... be aware that keyboard interrupts do NOT work...
exec /bin/bash -l

And /etc/exports:

/opt/netboot 192.168.1.0/255.255.255.0(ro,no_root_squash,insecure_locks,no_subtree_check)

And /tftpboot/pxelinux.cfg/default:

DEFAULT vmlinuz ip=dhcp root=/dev/nfs nfsroot=/opt/netboot init=/etc/init

The reason it seems I haven't progressed much since July is that I was getting those stale NFS file handles and didn't know how to solve it, so abandoned the nfsroot method at that time... it turned out, of course, that I wasn't specifying the right export options. Until my hard drive died a few days ago, I had been booting using an initrd, and mounting individual shares over NFS. Not much difference in the results, really, just another approach.

Back to blog or home page

last updated 2013-01-10 20:32:12. served from tektonic.jcomeau.com