zone transfers sticking on one port?

[Barry Margolin]

In article <c353jt$18a7$1 at sf1.isc.org>,
 Chris Fabri <fabric at northwestern.edu> wrote:

> I'm seeing what I think is an odd behavior with named, and want to know if 
> this is in fact how things should work.
> 
> We had blocked port 39999 on our border to help deal with the Beagle 
> virus.  We found out eventually that this was causing slave transfers to 
> from our nameserver to an off-site secondary to fail with the "failure 
> trying master error...:timed out"
> 
> I actually did a sniff, and I could just see all these UDP requests going 
> on on 39999 and not getting answered.   Other ports were obviously going 
> through ok.
> 
> Why was named hanging up on this port?    Shouldn't it just brush this off 
> and try another port >1023?     This doesn't make any sense to me.   chris 

When named starts up, it selects an unused high-numbered port to use as 
the source for its outbound queries.  It doesn't use a separate port for 
each query, as this would waste lots of ports unnecessarily.

-- 
Barry Margolin, barmar at alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***