Peer Heinlein: > Hi! > > Some mailservers close their session immediatley if the client-IP is > listed on RBLs or expected to come from a dynamic IP-range: > > p...@waffel:~> telnet 71.74.56.244 25 > Trying 71.74.56.244... > Connected to 71.74.56.244. > Escape character is '^]'. > 554 5.7.1 - ERROR: Mail refused - <89.204.137.69> - See > http://csi.cloudmark.com/reset-request/ > Connection closed by foreign host. > p...@waffel:~>
The server greets with 554 instead of 220. > In that case Postfix keeps his messages in the deferred-Queue even if > the recipients server has sent a 5xx fatal error: > > > Feb 17 00:55:28 91.198.250.29 postfix/smtp[9073]: 22210F6525: > to=<xx...@triad.rr.com>, relay=hrndvasmtpin02.mail.rr.com[71.74.56.244], > delay=1, status=deferred (host hrndva-smtpin02.mail.rr.com[71.74.56.244] > refused to talk to me: 554 5.7.1 - ERROR: Mail refused - > <213.203.238.10> - See http://security.rr.com/cgi-bin/block-lookup? > 213.203.238.10) > > I don't understand why Postfix does not bounce the message?! It's a > fatal error! This behavior is configurable, and the default is "safe". Wietse smtp_skip_5xx_greeting (default: yes) Skip SMTP servers that greet with a 5XX status code (go away, do not try again later). By default, the Postfix SMTP client moves on the next mail exchanger. Specify "smtp_skip_5xx_greeting = no" if Postfix should bounce the mail immediately. The default setting is incorrect, but it is what a lot of people expect to happen.
