Sahil Tandon: > On Sun, 04 Oct 2009, Ansgar Wiechers wrote: > > > On 2009-10-04 Sahil Tandon wrote: > > > On Sun, 04 Oct 2009, Ansgar Wiechers wrote: > > >> On 2009-10-04 mouss wrote: > > >> > > >>> anyway, it is ok to relay mail from the DMZ to the LAN. > > >> > > >> No. > > > > > > Why? > > > > Because violating the DMZ is never okay without a Damn Good Reason(tm). > > That's firewalling 101. If you allow inbound connections from untrusted > > to trusted networks, there's no point in having a DMZ in the first > > place. > > I appreciate the adherence to Firewalling 101 (something you have > preached before on security-basics), but common sense and practical > issues might impel one to make an exception and allow port 25 *only* > from Outside Postfix -> Inside Postfix. > > IMHO, of course. YMMV, TMTOWTDI and all other disclaiming acronyms.
If they really want no open ports, they can run UUCP between inside and outside machine, where inside polls the outside machine. Wietse