Quanah Gibson-Mount: > --On Thursday, March 31, 2016 9:15 PM -0400 Wietse Venema > <wie...@porcupine.org> wrote: > > >> Is this a known issue with Barracuda? Anyone have an idea how to work > >> around this? Clearly having their spam appliance be non-functional > >> isn't a great start. ;) > > > > Running Postscreen after a spam appliance is pointless. It is a > > spambot detector (in more sophisticated words, it implements IP > > address-based reputation). > > Ok. But I still would like to know where in the stack the problem is.
As Viktor says, they are violating SMTP (start talking inthe middle of a multi-line server response). Having a postscreen behind a mail relay is pointless. It would work if the spam appliance behaved like a proxy such as HaProxy or nginx that don't change the flow and timing of commands. But obviously that is not how Barracuda works. Wietse