MaraDNS stops resolving

[Sam Trenholme]

> I'm experiencing what Lars is talking about on NetBSD
> as well. So I do not believe it's a Linux Kernel specific
> issue.

Hmmm...again, I'm not seeing it.  How many client computers use your
server running MaraDNS?

But we may have a real probelm here.  The last time we saw something
like this, I was at a loss what was going on.  Finally, Albert Lee out
of the blue sent me a patch with the fix.  The problem was the Linux
kernel does not follow the POSIX spec with regard to the select()
call, and would hang programs when getting certain UDP packets unless
you did the right Linux-specific incantation.

So, as you can imagine, this problem is going to take a while to find
and fix.  It may be something simple or it may be something
unsolvable, such as "Many Unix kernels hang processes after spawning
1,000,000 threads" or some such.

Now, what I do have in order to help reproduce the bug is some tools
for seeing what is going on.  I developed these tools when getting
other similar reports.