Re: [Qemu-devel] TUN settings

[Tim <tim-qemu@sentinelchicken.org>]

> Here's my /etc/qemu-ifup script (based on what Tim posted):
> 
> !/bin/sh sudo /sbin/ifconfig tun0 192.168.2.200 netmask 255.255.255.0 
> broadcast 192.168.2.255
> sudo sh -c 'echo 1 > /proc/sys/net/ipv4/ip_forward'


on the first line... shouldn't that be broken into two?  
making it look something like:

#!/bin/sh
sudo /sbin/ifconfig tun0 192.168.2.200 netmask 255.255.255.0 broadcast 192.168.2.255
sudo sh -c 'echo 1 > /proc/sys/net/ipv4/ip_forward'


> And yet, I cannot ping the TUN interface in the host (192.168.2.200), and I 
> cannot ping anywhere else.

You probably know all of these things, but it doesn't hurt to check:

 - Your qemu-ifup script is executable by your user, yes?
 - /dev/net/tun exists (`MAKEDEV tun' has been run in /dev ??)
 - /dev/net/tun is writable by your user?
 - Your host OS's real ethernet card is configured to a different
   network than tun0, right?  You aren't going to be able to route (and
   ping may not even work) if you set tun0 and the guest OS to an IP in
   the same network range that your real NIC is a part of.

When QEMU is running, does ifconfig report the correct settings for
tun0?  

pardon me if this stuff is obvious to you,
tim