Le 15/02/2011 20:21, John a écrit : > First off I am still a bit green on this stuff. > > Both my servers are multi-homed, server A which runs Postfix is > configured -> eth0 :n.n.n.186 and eth1:n.n.n.187. > The host name for this server is mail.domain.tld which points to n.n.n.187. > > Up until last Friday we did not have any problems. On Friday we started > to get bounced when we tried to reply to a new contact at AT&T/Prodigy. > Their bounce message is as follows: > "host sbcmx5.prodigy.net[207.115.21.24] said: 553 5.3.0 flpd241 > DNSBL:ATTRBL 521< n.n.n.186 >>_is_blocked.__For_information_see_http://att.net/blocks (in reply to > MAIL FROM command". > A check of our logs shows only four message destined for their servers > in the last four weeks. I have check our servers using abuse.net and we > do not appear to be an open relay. None of the RBL have us listed. So I > do not think the problem is spamming. > > I think the problem is Postfix is sending using eth0, which in turn > means that it appears to come from n.n.n.186, which in turn means that a > reverse lookup does not resolve to mail.domain.tld. The loop is not > closed and therefor we are suspect.
then why not fix that? n.n.n.186 PTR foo.example.com n.n.n.187 PTR bar.example.com foo.example.com A n.n.n.186 bar.example.com A n.n.n.187 if that's not possible, then maybe n.n.n.186 PTR mail.example.com n.n.n.187 PTR mail.example.com mail.example.com A n.n.n.186 mail.example.com A n.n.n.187 > > I did some digging around I think that I need to modify my Postfix > configuration by adding "inet_interfaces=n.n.n.186, n.n.n.187, > localhost" and "smtp_bind_address=n.n.n.187". However this is where I > get a little confused as in one set of documents I have read it says to > add these into main.cf, while the postconf.5html say to leave the > inet_interface at default and add the smtp_bind_address the master.cf. to define the IP used to send mail, use smtp_bind_address. however, if you have mail that should go through another interface, then you'd better define two smtp transports and configure each with its smtp_bind_address (using -o), then setup transport entries to select which smtp to use. do not touch inet_interfaces unless you really need that. your example (inet_interfaces=ip1 ip2 localhost) looks useless. > [snip]
