From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Thu, 17 Sep 2009 16:10:55 -0700
From: Jerome Ibanes <jibanes@eskimo.com>
To: 9fans@9fans.net
Message-ID: <Pine.SUN.4.58.0909171547410.8301@eskimo.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Subject: [9fans] Netbooting from Qemu
Topicbox-Message-UUID: 71c142b6-ead5-11e9-9d60-3106f5b1d025

Hi,

I am (net)booting a Qemu instance from a Plan 9 fileserver named
colossus(192.168.1.40) running cwfs, an authserver, named
cerberus(192.168.1.50) is also present in the same domain.

The client is named cpu-003(192.168.1.33), it retrieves, via dhcp its
plan9.ini, which is as such:

  bootfile=ether0!/386/9pccpu.gz
  bootargs=tcp!192.168.1.40!564 -D
  fs=192.168.1.40
  auth=192.168.1.50
  sysname=cpu-003
  *nomp=1
  *debugload=1
  *nodumpstack=1

The dhcpd configuration uses /lib/ndb/local to properly serve dhcp
queries, relevants bits as follow:

  ipnet=drawterm.com ip=192.168.1.0 ipmask=255.255.255.0
    dnsdomain=drawterm.com
    authdom=drawterm.com
    ipgw=192.168.1.1
    dns=192.168.1.1
    ntp=192.168.1.1
    auth=cerberus
    fs=colossus
    cpu=cpu-001
    smtp=192.168.1.1

  ip=192.168.1.33 sys=cpu-003 ether=525400123456
    dom=drawterm.com
    bootf=/386/9pxeload
    proto=tcp

When booting a 9pc kernel (which means that bootfile=ether0!/386/9pc.gz)
the system boots, then prompt for a user login, secstore password and
behaves as a terminal, as one can expect.

When booting a 9pccpu kernel (with the configuration above, and not
another change from the 9pc kernel) the system hangs as such (please
notice that I have ipconfig debug mode turned on in the bootargs):

  [...]
  ipconfig: parsebootp: new packet
  ipconfig: parseoptions: type(53) len 1, bytes left 71
  ipconfig: parseoptions: lease(51) len 4, bytes left 68
  ipconfig: parseoptions: serverid(54) len 4, bytes left 62
  ipconfig: parseoptions: ipmask(1) len 4, bytes left 56
  ipconfig: parseoptions: ipgw(3) len 4, bytes left 50
  ipconfig: parseoptions: sys(12) len 12, bytes left 44
  ipconfig: parseoptions: dns(6) len 4, bytes left 30
  ipconfig: parseoptions: dom(15) len 3, bytes left 24
  ipconfig: parseoptions: ntp(42) len 4, bytes left 19
  ipconfig: parseoptions: <nil>(43) len 12, bytes left 13
  ipconfig: got ack from 192.168.1.40
  ipconfig: lease=1800
  ipconfig: ipaddr=192.168.1.33 ipmask=255.255.255.0
  ipconfig: ipgw=192.168.1.1
  ipconfig: dns=192.168.1.1
  ipconfig: ntp=192.168.1.1
  ipconfig: parseoptions: <nil>(128) len 4, bytes left 10
  ipconfig: parseoptions: <nil>(129) len 4, bytes left 4
  ipconfig: fs=192.168.1.40
  ipconfig: auth=192.168.1.50
  ipconfig: new ipaddr=192.168.1.33 new ipmask=255.255.255.0 new ipgw=192.168.1.1
  ipconfig: server=192.168.1.40 sname=colossus

Then the system hangs, the cwfs console reports that no connection was
established from cpu-003(192.168.1.33), while, when booting a 9pc kernel,
the connection is established and the boot sequence follows.

Finally, replacing 'tcp!192.168.1.40!564' by 'tcp' or 'tcp!colossus!564'
leads to the same results, I do not believe it to be a misconfiguration
however as 9pc is booting properly.

Despite that 9pccpu is hanging, I am able to ping this host
cpu-003(192.168.1.33) therefore the network card has been found and
initialized properly. A 'snoopy' reports that after the last dhcp queries,
no packets are ever sent from cpu-003(192.168.1.33).

What would cause this configuration to boot using a stock 9pc kernel but
not a 9pccpu one? I've even increased the memory allocation of the Qemu
instance as I would expect a 9pccpu kernel to be slightly bigger than a
9pc one.


Any suggestion?
  Jerome