On Monday 10 December 2007, Allen Weiner wrote:
> On Mon, 2007-12-10 at 22:28 -0500, Chris Knadle wrote:
> >    Makes no sense.  I don't think these are related.  /etc/resolv.conf
> > only relates to DNS, which is stuff on port 53.  Port 137 is for NETBIOS,
> > and which is nonroutable.  Are you perhaps using tunnelling like with a
> > VPN connection or something?
>
> I followed a suggestion from PorkChop to restore my original resolv.conf
> and see what happens. I restored resolv.conf to its original value and
> rebooted. The UDP traffic to port 137 has stopped.

   I still think it's unrelated to changes to /etc/resolv.conf.  As far s I 
know, port 137 of Netbios is only used by Windows machines in order to 
discover computer names and shares for showing things in the "Network 
Neighborhood".  The entry in /etc/serivces of 'netbios-ns' means "netbios 
name services" -- that's *NOT* directly related to DNS, even though it sounds 
like it could be.
   Were you doing anything with SMB shares or Samba before rebooting?

> As I mentioned to PorkChop, I'm a novice at networking. I'd *greatly*
> appreciate any additional suggestions you might have as to how to debug
> this.

   Ugh.  Well, generally speaking debugging networking means capturing network 
packets that your computer sees and examining them; usually followed by 
narrowing the parameters of the viewed packets to just the subset that show 
the problem.  Viewing raw packets is not easy to understand and is generally 
a job relegated to people doing networking professionally.
   There are several tools for doing this; the most common that I know of for 
the command line is 'tcpdump', and 'wireshark' or 'ksniffer' on the GUI side.  
I think a GUI program will be easier for you to use, but I've never used 
them.  'tcpdump' is somewhat user-hostile before you get used to its command 
line option quirks.

   Besides packet sniffing you can also look at what network ports your box 
has open with 'netstat -tu'.  If you run 'netstat -tup' as root you'll also 
see what program is associated with every open network connection.  [The -tu 
means TCP and UDP; this is to not show local connections on unix sockets.]

   Well that's a start anyway.
   -- Chris

-- 

Chris Knadle
[EMAIL PROTECTED]

Attachment: signature.asc
Description: This is a digitally signed message part.

_______________________________________________
Mid-Hudson Valley Linux Users Group                  http://mhvlug.org          
   
http://mhvlug.org/cgi-bin/mailman/listinfo/mhvlug                           
Upcoming Meetings (6pm - 8pm)                         MHVLS Auditorium          
                              
  Dec 5 - Open Source Show and Tell
  Jan 2 - TBD
  Feb 6 - DBUS
  Mar 5 - Setting up a platform-independent home/small office network using 
Linux

Reply via email to