is there a possibility to set the SMTP Proxy for only internal usage, so that requests from external are bloked by packetfilter? I didn't find a point to set the allowed networks.
you can easily achieve this by providing no upstream hosts/networks in the Relaying tab and below the upstream host/network list check the checkbox labeled "Allow upstream/relay hosts only".
you can easily achieve this by providing no upstream hosts/networks in the Relaying tab and below the upstream host/network list check the checkbox labeled "Allow upstream/relay hosts only".