[9fans] the JD project: little tiny liinux that is a driver for Plan 9, boots in seconds.

["ron minnich" <rminnich@gmail.com>]

It is called JD for a reason  ...

anyway ...

on sources/xen/xen3/xentest.tgz is the latest.

here is what it does
boots a minimal linux to a bash prompt. You type
xend start
xm create hanska
this in turn boots a cpu server under xen which tries to mount from an
fs, which does not exist, but hey ... it can start up a plan 9
instance. And give it an IP from DHCP. And it tries and fails to mount
an fs from somewhere. And if finds the block device (sd00). This is
close.

The linux will nat for you.

In theory, I should be able to mount 9grid.net, have not tried this yet.

The file is a mere 62M compressed (sorry!) but we're trying. I had to
pull in lots of shit because the xen scripts are a mix of python and
bash. The bash scripts, if written in python, would not need all the
shit. Long term, they should all be python, and I am sure that you
folks are chomping at the bite to rewrite them, python being such a
readable, simple, easy to bug-insert language (what's the oppose of
debug? Where you insert a bug just be removing whitespace? maybe embug
-- for embedding a bug. )

here is my grub.conf entry for it -- see, I'm getting user-friendly
this time around.

title           tiny horrible xen
root            (hd0,5)
kernel          /boot/xen-3.0.3-1-i386.gz
module          /boot/vmlinuz-2.6.18-3-xen-686 root=/dev/hda6 ro console=tty0
module          /boot/initrd.img-2.6.18-3-xen-686

So, what did it take to make this work?

Oh, not much. Xen reported hotplug failing, in a way calculated to confuse me.

But, thinks I, I need udev. But, udev won't start without syslog in
there. Honest, strace doesn't lie.

So, in the end, I added:
[root@q rminnich]# ls /xentest/etc/init.d/
functions  syslog
[root@q rminnich]#

[root@q rminnich]# ls /xentest/etc/
blkid.tab      dhcpd.conf  hosts    hotplug.d  localtime  passwd
syslog.conf  xen
blkid.tab.old  fstab       hotplug  init.d     mtab       services  udev
[root@q rminnich]#

rm /etc/mtab; ln -s /proc/mounts /etc/mtab

[root@q rminnich]# ls /xentest/lib | wc
    125     125    193
[root@q rminnich]# ls /xentest/usr/lib
libsysfs.so.1  libz.so.1  libz.so.1.2.3  python2.4  xen-3.0.3-1
xen-common  xen-default
[root@q rminnich]# ls /xentest/bin
basename  hanska   mv         sed      umount       xenctx
xenstore-read
bash      ip       netfix     sh       usleep       xend
xenstore-rm
cat       killall  ps         sleep    xc_restore   xenmon.py
xenstore-write
cp        less     pygrub     stat     xc_save      xenperf           xentop
cut       logger   readlink   strace   xc_shadow    xenstore-chmod    xentrace
dhcpd     lomount  readnotes  sync     xenbaked     xenstore-control
xentrace_format
drawterm  ls       reset      tcpdump  xen-bugtool  xenstored
xentrace_setmask
ed        mkdir    rm         touch    xencons      xenstore-exists
xentrace_setsize
expr      mktemp   rmdir      tr       xenconsole   xenstore-list     xm
grep      mount    runme      true     xenconsoled  xenstore-ls
[root@q rminnich]# ls /xentest/usr/bin/
awk  dirname  env  python
[root@q rminnich]# ls /xentest/sbin/
brctl        initlog           jfs_fscklog  nologin  udevcontrol
 udevstart.static
consoletype  insmod            jfs_logdump  pidof    udevd
 udev.static
depmod       iptables          klogd        sh       udev_run_devd
getty        iptables-restore  logsave      sulogin  udev_run_hotplugd
ifconfig     iptables-save     losetup      syslogd  udevsend
init         isdnlog           modprobe     udev     udevstart
[root@q rminnich]#


and a few other bits. If you think this is a lot, you haven't been
watching linux lately.

Also, the following simple thing:
[root@q rminnich]# cat /xentest/bin/runme
#!/bin/sh -x
mount -t tmpfs none /tmp
mount -t tmpfs none /var
mkdir -p /var/run/xenstored
mkdir -p /var/log/xen
mkdir -p /var/log/hotplug
mkdir -p /var/lib
mkdir -p /var/lib/dhcp
touch /var/lib/dhcp/dhcpd.leases
mkdir -p /var/lock/subsys
mkdir -p /var/run/xen-hotplug

PATH=$PATH:/usr/lib/xen-3.0.3-1/bin
export PATH

/etc/init.d/syslog start
/sbin/udevd&
modprobe loop
modprobe bridge
modprobe netloop
ipconfig eth0 10.0.0.1 up
#xend start
#xm create hanska &
PATH=$PATH:/mnt

ah, well, we had hoped to have a readonly medium, but we have not
resolved the problem of a writeable root for plan 9. maybe later. What
would be very interesting is to not have a root at all, but just boot
as a terminal from somewhere, but we are not ready yet. But that is
the Dream.

anyway, 20M are there, 40M need to get there, so give it a few
minutes. The file when done is this:

[root@q xentest]# ls -l /tmp/xentest.tgz
-rw-r--r--  1 root root 62174680 Dec 20 15:48 /tmp/xentest.tgz
[root@q xentest]#

testers welcome, as long as you're not too helpless when confronted
with Xen ... it's not ready for that yet!

thanks


ron