Firewall Wizards mailing list archives
RE: RE: Help w/ Port 137 Traffic
From: Frank Knobbe <fknobbe () knobbeits com>
Date: 13 Oct 2002 21:15:53 -0500
On Sun, 2002-10-13 at 12:52, Stefan Norberg wrote:
I tend to build firewall rulebases that does the following (don't know if this is common practice/knowledge out there): 1) Accept rules for traffic to the firewall device itself go first (such as ssh, fw-gui). 2) Explicit drop for all other traffic to the firewall device. 3) General accept rules (ordered by system - high volume stuff first). 4) Silent drop of some stuff that just fills up the logs and add litte value, such as udp/137. Drop certain internal ip's that scans the internal network all the time. And so on. 5) Drop and log everything else. In general you don't want to use block/reject, since it sends out a TCP RST (for TCP) or ICMP port unreach for UDP. An example where you would you block/reject is to avoid timeouts for valid traffic such as identd.
Stefan, I build mine very similar to you, with one exception. Any traffic from the inside net that the firewall is supposed to block, I'm REJECTing. That way internal devices don't 'hang' waiting for a timeout. Everything coming in from the outside still gets DROPPED though. But I do prefer to send a RST to hosts on the inside. Regards, Frank
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Current thread:
- Re: Help w/ Port 137 Traffic, (continued)
- Re: Help w/ Port 137 Traffic Paul D. Robertson (Oct 13)
- Re: Help w/ Port 137 Traffic Mikael Olsson (Oct 13)
- Re: Help w/ Port 137 Traffic Paul D. Robertson (Oct 13)
- Re: Help w/ Port 137 Traffic Mikael Olsson (Oct 13)
- Re: Help w/ Port 137 Traffic Paul D. Robertson (Oct 13)
- Re: Help w/ Port 137 Traffic Mikael Olsson (Oct 13)
- Re: Help w/ Port 137 Traffic Vincent Haverlant (Oct 15)
- Re: Help w/ Port 137 Traffic Mikael Olsson (Oct 13)
- Re: Help w/ Port 137 Traffic Paul D. Robertson (Oct 13)
- RE: RE: Help w/ Port 137 Traffic Stefan Norberg (Oct 13)
- RE: RE: Help w/ Port 137 Traffic Frank Knobbe (Oct 13)
- RE: RE: Help w/ Port 137 Traffic Stefan Norberg (Oct 14)
- Re: RE: Help w/ Port 137 Traffic Devdas Bhagat (Oct 14)
- Re: RE: Help w/ Port 137 Traffic R. DuFresne (Oct 14)