Problem when making a domain

Problem when making a domain

[aq]

Hello,

I am trying to make the first domain. I follow the demo in Xen manual,
by getting the minimalist ttylinux. Here is my configuration file:

--------
$ more tty.xm 
kernel = "/boot/vmlinuz-2.6.9-xenU"
memory = 64
name = "ttyDomain"
disk = [ 'file:~/myxen/rootfs,hda1,w' ]
root = "/dev/hda1 ro"
ip = "192.168.1.222"
netmask = "255.25.255.0"
gateway = "192.168.1.1"
--------

In that file, rootfs is from ttylinux tarball.

Then I make the domain with that configuration file, but I got the
error. Here is the excerpt:

-------
$ xm create tty.xm -c
...
Starting fsck for root filesystem.
e2fsck 1.35 (28-Feb-2004)
Couldn't find ext2 superblock, trying backup blocks...
fsck.ext2: Invalid argument while trying to open /dev/ram0

The superblock could not be read or does not describe a correct ext2
filesystem.  If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
    e2fsck -b 8193 <device>

WARNING: Errors found while checking root filesystem.
You can login as root now, the system will reboot after logout.

Give root password for system maintenance
(or type Control-D for normal startup):
--------

Then I must enter "root" as root password to login. Could you tell me
how to fix this "maintenance system" problem?


One more thing I notice: in the configuration file, following the manual, I set:

root = "/dev/hda1 ro"

Is that fine? I am afraid that it makes the root filesystem read-only,
so once logging in, I cannot modify anything inside ?

Thank you a lot,
AQ


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/

Re: Problem when making a domain

[Keir Fraser]

> In that file, rootfs is from ttylinux tarball.

Doesn't look like it from your boot messages. It's either a garbage
file, or it needs decompressing.

> One more thing I notice: in the configuration file, following the manual, I set:
> 
> root = "/dev/hda1 ro"
> 
> Is that fine? I am afraid that it makes the root filesystem read-only,
> so once logging in, I cannot modify anything inside ?

It'll get remounted writable during startup, after the filesystem is
successfully fsck'ed.

 -- Keir


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/

Re: Problem when making a domain

[aq]

Hello,

> Doesn't look like it from your boot messages. It's either a garbage
> file, or it needs decompressing.
Really I dont think the rootfs is wrong. I got rootfs.gz from the
ttylinux tarball, and just "gunzip" it.

The same problem happen with my slackware file system. This slackware
is in a separate partition /dev/hda3 (my machine is dualboot, together
with Ubuntu - the current in use environment). Here is my
configuration file for the slackware partition:

---
$ more slack.xm 
kernel = "/boot/vmlinuz-2.6.9-xenU"
memory = 128
name = "slackDomain"
disk = [ 'phy:hda3,hda1,w' ]
root = "/dev/hda1 ro"
ip = "192.168.1.222"
netmask = "255.255.255.0"
gateway = "192.168.1.1"
extra = "4"
---

And here is excerpt from bootup process. The problem occur at the end:
----
...
[XEN:vbd_update:drivers/xen/blkfront/blkfront.c:194] >
[XEN:vbd_update:drivers/xen/blkfront/blkfront.c:195] <
EXT3-fs: mounted filesystem with ordered data mode.
VFS: Mounted root (ext3 filesystem) readonly.
Freeing unused kernel memory: 92k freed
kjournald starting.  Commit interval 5 seconds
modprobe: FATAL: Could not load /lib/modules/2.6.9-xenU/modules.dep:
No such file or directory

modprobe: FATAL: Could not load /lib/modules/2.6.9-xenU/modules.dep:
No such file or directory

INIT: version 2.84 booting
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
Initializing udev dynamic device directory.
swapon: cannot stat /dev/hda2: No such file or directory
Testing root filesystem status:  read-only filesystem
Checking root filesystem:
fsck 1.35 (28-Feb-2004)
/sbin/e2fsck: No such file or directory while trying to open /dev/hda3
/dev/hda3: 
The superblock could not be read or does not describe a correct ext2
filesystem.  If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
    e2fsck -b 8193 <device>


***********************************************************
*** An error occurred during the root filesystem check. ***
*** You will now be given a chance to log into the      ***
*** system in single-user mode to fix the problem.      ***
***                                                     ***
*** If you are using the ext2 filesystem, running       ***
*** 'e2fsck -v -y <partition>' might help.              ***
***********************************************************

Once you exit the single-user shell, the system will reboot.


Type control-d to proceed with normal startup,
(or give root password for system maintenance):
----

Can you give me some advice to fix this error?

Thank you a lot,
AQ


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/

Re: Problem when making a domain

[Steven Hand]

>disk = [ 'phy:hda3,hda1,w' ]
>root = "/dev/hda1 ro"

[snip] 

>swapon: cannot stat /dev/hda2: No such file or directory
>Testing root filesystem status:  read-only filesystem
>Checking root filesystem:
>fsck 1.35 (28-Feb-2004)
>/sbin/e2fsck: No such file or directory while trying to open /dev/hda3
>/dev/hda3: 


Your /etc/fstab in the /dev/hda3 filesystem is expecting root
to be on /dev/hda3 (and swap to be on /dev/hda2) but you've 
chosen to export /dev/hda3 to it as /dev/hda1

Easiest thing is to use

disk = [ 'phy:hda3,hda3,w' ]
root = "/dev/hda3 ro"

in your vm config file. 

If you want to use your swap partition and you're not using it 
from domain0, you can export that too: 

disk = [ 'phy:hda3,hda3,w', 'phy:hda2,hda2,w']

cheers,

S.



-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/

Re: Problem when making a domain

[aq]

Hello,

> > Doesn't look like it from your boot messages. It's either a garbage
> > file, or it needs decompressing.
>
> You could try running file(1) on it to determine type.

I check again the rootfs, and found nothing wrong, like below
---
$ file rootfs
rootfs: Linux rev 1.0 ext2 filesystem data
---

I can even mount the rootfs (with -o loop), and found all the data
inside it in perfectly shape.

One more thing I noticed in the bootup message is:
---
fsck.ext2: Invalid argument while trying to open /dev/ram0
---

It seems the bootup process tried to check /dev/ram0? why is that? I
expect it would check /dev/hda1, like what I declared in my
configuration file (!!??)

Please help me. I struggle a lot at this step. Making a first domain
in Xen looks tedious for me ;-)

I posted again my configuration file (which follows the demo in the
2.0 manual, with ttylinux as rootfs).

Here is my configuration file:
----
$ cat tty.xm
kernel = "/boot/vmlinuz-2.6.9-xenU"
memory = 64
name = "tty"
disk = [ 'file:~/myxen/rootfs,hda1,w' ]
root = "/dev/hda1 ro"
----

And finally here is the excerpt of bootup message. It always ask me to
enter root password then it enters System maintenance mode, which
mounts / as read-only:

----
...
Starting fsck for root filesystem.
e2fsck 1.35 (28-Feb-2004)
Couldn't find ext2 superblock, trying backup blocks...
fsck.ext2: Invalid argument while trying to open /dev/ram0

The superblock could not be read or does not describe a correct ext2
filesystem.  If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
    e2fsck -b 8193 <device>

WARNING: Errors found while checking root filesystem.
You can login as root now, the system will reboot after logout.

Give root password for system maintenance (or type Control-D for
normal startup):

----

Best regards,
AQ


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/