Il 22 marzo 2019 21:31:40 CET, bruno.carva...@xervers.pt ha scritto: >Thank you all for your suggestions. >I will follow the path of using a whitelist and block everyone. >I can track the IPs, but i taught i could put in place something (like >OVH by example) do (If their system detects spam being sent, the port >on that ip is automatically blocked and the client alerted). > >Cheers > > >Bruno Carvalho (CEO xervers) | +41 79 884 00 44 > Please consider the environment before printing this email > > > > >-----Mensagem original----- >De: Benny Pedersen <m...@junc.eu> >Enviada: sexta-feira, 22 de março de 2019 20:55 >Para: users@spamassassin.apache.org >Assunto: Re: Filtering at border routers: Is it possible? > >Anthony Hoppe skrev den 2019-03-22 18:23: >> Not knowing the details of your environment... >> >> Instead of taking on the job of filtering email for all of your >> clients (this, to me, will open up a can of worms), why not set a >> policy that port 25 is blocked by default and customers must request >> for it to be unblocked? > >dont relay mail from port 25, mails there is final recipient only, not >forwared > >> You can then build a list of who may be using your services to send >> mail and better track if/when undesirable mail is sent from your >> network? > >ask custommers to use port 587 or 465 as common pratice > >but do require sasl auth on this ports, reject all else > >sadly i see mtas try to use 587, and 465, i like to know with book thay >read
Hi, this is what OVH does (article in french, sorry): https://www.numerama.com/magazine/26297-ovh-copie-et-analyse-tous-les-e-mails-sortant-de-ses-serveurs.html Giovanni