[120872] in North American Network Operators' Group
Re: I don't need no stinking firewall!
daemon@ATHENA.MIT.EDU (Jay Hennigan)
Tue Jan 5 16:22:49 2010
Date: Tue, 05 Jan 2010 13:18:47 -0800
From: Jay Hennigan <jay@west.net>
To: nanog@nanog.org
In-Reply-To: <AFD31EAF2DD7F346AA17E164615555B0321B3280@SVR-AMED-MAIL01.amedisys.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Jason Shearer wrote:
> Doesn't using the established allow any packet with ACK/RST set
Yes, as would be expected for legitimate return traffic for a TCP
connection initiated from a browser inside the firewall.
> and wouldn't you have to allow all high ports?
That's what the ">" is for. Cisco syntax "gt" (greater than).
The point is that either of these will deny unsolicited new connection
attempts from the outside to TCP 22 (and 445, 135, etc.)
--
Jay Hennigan - CCIE #7880 - Network Engineering - jay@impulse.net
Impulse Internet Service - http://www.impulse.net/
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