So there is the -y option that should avoid that kind of problem... Tried with --force-yes and it doesn't works neither. I removed the </dev/null and know fai-setup stops and ask me if I want to overwrite the config file, I simply say "Y" and it works.
I read /usr/sbin/ make-fai- nfsroot script to see what's going on. I see that packages are installed by the following command:
$ROOTCMD apt-get -y --fix-missing install $packages </dev/null
So there is the -y option that should avoid that kind of problem... Tried with --force-yes and it doesn't works neither. I removed the </dev/null and know fai-setup stops and ask me if I want to overwrite the config file, I simply say "Y" and it works.
I don't understand what's the problem...