[Qemu-devel] Tap network reloading

[Clemens Kolbitsch <ck@iseclab.org>]

Hi list,

I am using Qemu (with kqemu and virtual tap device) in a system to analyze 
binaries. In this system, I have to start qemu very often with only very short 
periods (around 10-15 seconds) in between.

Although Qemu itself does not have problems with it, I *very* often (i.e. 9 
out of 10 times) see that the networking inside the guest is not accessible 
from the outside nor the other way around for some time when loading a 
snapshot.

So, when I start qemu, let it run for a few minutes, quit and restart Qemu and 
load a snapshot, I cannot ping the guest network nor can I access the host (or 
anything else for that matter) from inside the guest. After 1-2 minutes, 
suddenly networking starts working. All other (non network-related) things 
work fine right from the start.

I am running Qemu on a (Ubuntu) 2.6.28-11 linux host and a WinXP guest.
Maybe someone has experience with this and can help me, what would greatly be 
appreciated :-)

Clemens