Comment 12 for bug 839492

halfgaar wrote:
> Do you get kernel messages when you do that?

Only the first time after boot, yes:

[...]
Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done.
Gave up waiting for root device. Common problems:
 - Boot args (cat /proc/cmdline)
   - Check rootdelay= (did the system wait long enough?)
   - Check root= (did the system wait for the right device?)
 - Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/xvda2 does not exist. Dropping to a shell!

BusyBox v1.17.1 (Ubuntu 1:1.17.1-10ubuntu1) built-in shell (ash)
Enter 'help' for a list of built-in commands.

(initramfs) modprobe xen-blkfront
[ 44.986269] blkfront device/vbd/51714 num-ring-pages 1 nr_ents 32.
[ 44.989583] blkfront device/vbd/51713 num-ring-pages 1 nr_ents 32.
[ 44.995041] Initialising Xen virtual ethernet driver.
(initramfs) exit
Gave up waiting for root device. Common problems:
 - Boot args (cat /proc/cmdline)
   - Check rootdelay= (did the system wait long enough?)
   - Check root= (did the system wait for the right device?)
 - Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/xvda2 does not exist. Dropping to a shell!

BusyBox v1.17.1 (Ubuntu 1:1.17.1-10ubuntu1) built-in shell (ash)
Enter 'help' for a list of built-in commands.

(initramfs) modprobe xen-blkfront
(initramfs) exit
Gave up waiting for root device. Common problems:
 - Boot args (cat /proc/cmdline)
   - Check rootdelay= (did the system wait long enough?)
   - Check root= (did the system wait for the right device?)
 - Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/xvda2 does not exist. Dropping to a shell!

BusyBox v1.17.1 (Ubuntu 1:1.17.1-10ubuntu1) built-in shell (ash)
Enter 'help' for a list of built-in commands.
[...]

ls /dev/ doesn't show anything starting with x at all, even after the
modprobe:

Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done.
Gave up waiting for root device. Common problems:
 - Boot args (cat /proc/cmdline)
   - Check rootdelay= (did the system wait long enough?)
   - Check root= (did the system wait for the right device?)
 - Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/xvda2 does not exist. Dropping to a shell!

BusyBox v1.18.4 (Ubuntu 1:1.18.4-2ubuntu2) built-in shell (ash)
Enter 'help' for a list of built-in commands.

(initramfs) modprobe xen-blkfront
[ 34.544021] blkfront device/vbd/51714 num-ring-pages 1 nr_ents 32.
[ 34.547113] blkfront device/vbd/51713 num-ring-pages 1 nr_ents 32.
[ 34.550799] Initialising Xen virtual ethernet driver.
(initramfs) ls /dev
vga_arbiter tty28 hvc5 ram9
rfkill tty29 hvc6 ram10
mem tty30 hvc7 ram11
null tty31 ttyS0 ram12
port tty32 ttyS1 ram13
zero tty33 ttyS2 ram14
full tty34 ttyS3 ram15
random tty35 ttyS4 loop0
urandom tty36 ttyS5 loop1
kmsg tty37 ttyS6 loop2
oldmem tty38 ttyS7 loop3
tty tty39 ttyS8 loop4
console tty40 ttyS9 loop5
tty0 tty41 ttyS10 loop6
vcs tty42 ttyS11 loop7
vcsa tty43 ttyS12 ppp
vcs1 tty44 ttyS13 net
vcsa1 tty45 ttyS14 usbmon0
tty1 tty46 ttyS15 input
tty2 tty47 ttyS16 psaux
tty3 tty48 ttyS17 uinput
tty4 tty49 ttyS18 mapper
tty5 tty50 ttyS19 cpu_dma_latency
tty6 tty51 ttyS20 network_latency
tty7 tty52 ttyS21 network_throughput
tty8 tty53 ttyS22 pts
tty9 tty54 ttyS23 core
tty10 tty55 ttyS24 fd
tty11 tty56 ttyS25 stdin
tty12 tty57 ttyS26 stdout
tty13 tty58 ttyS27 stderr
tty14 tty59 ttyS28 btrfs-control
tty15 tty60 ttyS29 block
tty16 tty61 ttyS30 char
tty17 tty62 ttyS31 vcs2
tty18 tty63 ttyprintk vcsa2
tty19 snapshot ram0 vcs3
tty20 ecryptfs ram1 vcsa3
tty21 fuse ram2 vcs4
tty22 ptmx ram3 vcsa4
tty23 hvc0 ram4 vcs5
tty24 hvc1 ram5 vcsa5
tty25 hvc2 ram6 vcs6
tty26 hvc3 ram7 vcsa6
tty27 hvc4 ram8

> Do you do it from the recovery initramfs shell?

Sure, where else?

> Do you type exit afterwards?

I prefer to press Ctrl-D instead, but yes.

> Does your vmname.cfg on the dom0 have the xvda devices listed?

Do you mean the configuration for the DomU? If so, yes:

80/1/0 root@acromantula:pts/0 20:51:10 [~] # cat /etc/xen/acromantula-domu1.cfg
#
# Configuration file for the Xen instance acromantula-domu1, created
# by xen-tools 4.2.1+dev on Wed Sep 14 19:59:50 2011.
#

#
# Kernel + memory size
#

bootloader = '/usr/lib/xen-default/bin/pygrub'

vcpus = '1'
memory = '128'

#
# Disk device(s).
#
root = '/dev/xvda2 ro'
disk = [
                  'phy:/dev/vg0/acromantula-domu1-disk,xvda2,w',
                  'phy:/dev/vg0/acromantula-domu1-swap,xvda1,w',
              ]

#
# Physical volumes
#

#
# Hostname
#
name = 'acromantula-domu1'

#
# Networking
#
dhcp = 'dhcp'
vif = [ 'mac=00:16:3E:AF:50:8A' ]

#
# Behaviour
#
on_poweroff = 'destroy'
on_reboot = 'restart'
on_crash = 'restart'

  Regards, Axel
--
 ,''`. | Axel Beckert <email address hidden>, http://people.debian.org/~abe/
: :' : | Debian Developer, ftp.ch.debian.org Admin
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