The Sendmail Solution

• Closed down the open relay

  • FEATURE(`blacklist_recipients')dnl
  • FEATURE(`relay_based_on_MX')dnl
  • FEATURE(dnsbl, `rbl.maps.vix.com', `Mail from $&{client_addr} Rejected - see http://www.mail-abuse.org/rbl/')dnl
  • FEATURE(dnsbl, `dialups.mail-abuse.org', `Dialup - see http://www.mail-abuse.org/dul/')dnl
  • FEATURE(dnsbl, `relays.mail-abuse.org', `Open spam relay at $&{client_addr} - see http://www.mail-abuse.org/rss/')dnl
  • FEATURE(`delay_checks')dnl

• Use SMTP AUTH instead of the access file

  • SMTP AUTH allows relaying for senders who have successfully authenticated themselves.