Name resolution with Sinus-111 wireless DSL router

[Doubletwist]

Thomas Hühn wrote:
> Hi
> 
> I use a Sinus-111 DSL router which also acts as a caching DNS.
> 
> Reproducibly it stops resolving any name whenever Ubuntu has been in the 
> network. That also means that downloading security updates etc. while 
> installing fails.
> 
> The only way I've found so far to make it work again is to reboot the 
> router. Until Ubuntu is booted again. :-/
> 
> What's so special about Ubuntu? Debian testing works flawlessly, for 
> example. Also Fedora Core.
> 
> <1098181845.5771.14.camel at localhost.localdomain> ("DNS issues") mentions 
> similar but, I think, still other problems (resolution fails completely 
> here, I don't add servers to resolv.conf).
> 
> Thomas
> 

It may not be even remotely related but I had a vaguely similar problem 
once with a linksys print server. Any time I would try to connect to the 
printer from my debian box, the print server would stop working until it 
was restarted. Everyone elses system worked fine with it [Windows, Suse, 
Slackware, Gentoo].
It turned out that one of my firewall rules, which was dropping unclean 
packets, was the culprit. I guess the printserver was responding with an 
unclean packet [don't know why], which my firewall dropped leaving the 
printserver hanging and not answering any requests from anyone.
As soon as I removed the rule to drop unclean packets, it worked fine.

So you might want to look into areas like that for possible causes. 
[Even though I'm sure the installer isn't running iptables].

DT