On Tue, 15 Aug 2006, Guy Waugh wrote: > > Aug 15 05:01:35 mailserver sendmail[13287]: k7EJ1YE7013287: SYSERR(root): > localhost.fabulous.com. config error: mail loops back to me (MX problem?) > > Do people actively combat this somehow?
Exim has a feature ignore_target_hosts which causes it to strip certain IP addresses from the list of MX hosts for a domain. I use it to block all abusive or unreachable MXs (listed below). This kicks in when Exim is doing address verification at SMTP time, for example "sender verify fail for <[EMAIL PROTECTED]>: all relevant MX records point to non-existent hosts" 0.0.0.0/8 # this net 10.0.0.0/8 # RFC 1918 127.0.0.0/8 # this host 169.254.0.0/16 # link-local 172.16.0.0/12 # RFC 1918 192.0.2.0/24 # example net 192.168.0.0/16 # RFC 1918 198.18.0.0/15 # benchmark net 224.0.0.0/3 # multicast & reserved It would probably be good to augment this list with bogon or hijacked address space, but then it would be more work to keep up-to-date. Tony. -- f.a.n.finch <[EMAIL PROTECTED]> http://dotat.at/ FISHER: WEST OR NORTHWEST 4 OR 5 BECOMING VARIABLE 3 OR 4. FAIR. MODERATE OR GOOD.
