Re: uml on sarge

[Nelson Castillo <nelsoneci@gmail.com>]

Hi.

mdk:~# apt-cache search ^uml
gaphor - UML modeling tool
umbrello - UML modelling tool and code generator
uml-utilities - User-mode Linux (utility programs)
mdk:~#

> uml-utilities

"uml-utilities" is the only one available from sarge. Maybe you installed
the other packages from unstable. I installed uml-utilities from sarge and
built the uml binary (the kernel that runs in user space) from
kernel-source-2.6.10 (unstable).

> umlrun
> umlrun-uml
> user-mode-linux
> 
> When as normal user I try:
> $ linux
> 
> I get a kernel panic (In UML) saying can't mount the root device.

...

> I installed rootstrap and tried to create a rootfs image but it isn't able to
> create,

Well.  Tell us how you called it and what the error messages are.
I have the newly created rootfs image (86MB bzip2) and it would be
nice to post it somewhere. My hosting is not big.

Remember you have to copy the new system to a
partition(ext2/ext3/something else).

>I suspect that I'm not able to configure the network part.
> The documentation for it are missing.

It's in the howto... Kinda difficult sometimes.

> I also downloaded the "Debian-3.0r0.ext2" fs image from sourceforge and tried
> to use it using:
> 
> $ linux ubd0=Debian-3.0r0.ext2
> 
> It boots but gives error saying it can't fsck the filesystem.
>Is it really that difficult to setup uml in Debian ??

The networking part has been the hardest for me. It took me a lot of time
to get it working :(

As root I use:

USER=***UML-USER***
IP=***MYIP***
tunctl -t uml0 -u $USER
ifconfig uml0 192.168.0.1 netmask 255.255.255.0
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A POSTROUTING -s 192.168.0.0/255.255.255.0 -o eth0 -j
SNAT --to-source $IP
chmod 666 /dev/net/tun # DOS ATTACK!!! USE A GROUP.

As the UML user I run:

uml_switch -tap uml0

And then

./linux eth0=daemon (more parameters)

> Or am I missing something ??

We always do :)

Regards,
Nelson.-