Re: IPSec Paketfilter für Mailserver (MDaemon)

From: Markus Mühlich (markus.muehlicht_at__net_cologne.de)
Date: 03/25/04 

Date: Thu, 25 Mar 2004 19:11:07 +0100

Hallo Christoph,

vielen Dank für Deine Antwort.

> Traffic nach Port 53 TCP & UDP muss frei sein.

Ja habe ich gemacht. Neben den bereits erwähnten Filterregeln bestehen auch
zwei für DNS:

Port 53 - TCP - eingehend - zulassen
Port 53 - UDP - eingehend - zulassen.

Das Ergbenis bleibt jedoch. Der Mailserver erhält keine Antwort weil diese
wohl auf einem anderen UDP Port ankommt, die eben durch den generellen
Filter blockiert wird. Ändere ich hingegen den Filter, daß er UDP auf allen
Ports durchläßt, hat der Mailserver keine Probleme.

Habe ich irgendeine Möglichkleit festzustellen über welchen Port dieser UDP
Verkehr reinkommt?

Danke
Markus

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