Michelle Sullivan matthew at
Sat Feb 20 17:31:24 UTC 2010

Scott Howard wrote:
> On Fri, Feb 19, 2010 at 5:20 PM, William Herrin <bill at> wrote:
>> On Fri, Feb 19, 2010 at 3:30 PM, Rich Kulawiec <rsk at> wrote:
>>> Barracuda's engineers apparently think
>>> that using SPF stops backscatter -- and it most emphatically does not.
>>> Reject gooooood, bounce baaaaaaad. [1]
>> Whine all you want about backscatter but until you propose a
>> comprehensive solution that's still reasonably compatible with RFC
>> 2821's section 3.7 you're just talking trash.
> In the case of Barracuda's long history of Backscatter the solution is
> simple, and is implemented by most other mail vendors - it's called
> "Don't accept incoming mail to an invalid recipient".
> Barracudas used to have no way of doing address validation for
> incoming mail, so they would accept it and then bounce it when the
> next hop (eg, the Exchange server) rejected the recipient address.
> They finally fixed this a few years ago, and can not integrate with
> LDAP (and possibly others) for address validation. Of course, it's
> still down to the admin to implement it...

Actually they do (did?), as they run postfix, they should be
configurable to use LDAP and a whole host of other methods.


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