Subject: ipv6 reverse name server vs. ftp
To: None <tech-net@netbsd.org>
From: Steven M. Bellovin <smb@cs.columbia.edu>
List: tech-net
Date: 06/28/2005 14:42:16
A couple of my v6-capable machines don't seem to be listed in a
functional reverse name server. That is, there is no working server
that maps IPv6 addresses to host names. (Yes, I'm trying to deal with
that.) Worse yet, as best I can tell there's a non-functional server;
attempts to resolve the PTR record time out. This in turn causes
problems with using ftp -- the ftp server on ftp.netbsd.org tries to
look up the name; it takes sufficiently long to fail that (as best I
can tell) my client times out: ftp.c seems to have a fixed 60-second
timer before it gives up on the connection.
I'm not certain how best to fix this. Clearly, I should try to get my
name server fixed. The odds on that happening are, I think, reasonable.
Others won't be that lucky. Should we fix the timers on our ftp
server? On our clients? Both?
--Steven M. Bellovin, http://www.cs.columbia.edu/~smb