Scott Talbert: > On Sun, 9 Jul 2017, Wietse Venema wrote: > > >> Jul 7 23:10:57 bear postfix/smtp[29598]: 92F8422A0C90: to=<a...@xyz.com>, > >> relay=aspmx.l.google.com[2607:f8b0:400d:c0b::1a]:25, delay=0.65, > >> delays=0.13/0/0.29/0.22, dsn=5.7.1, status=bounced (host > >> aspmx.l.google.com[2607:f8b0:400d:c0b::1a] said: 550-5.7.1 > >> [2607:f308:1:1::2 12] Our system has detected that this message > >> 550-5.7.1 is likely unsolicited mail. To reduce the amount of spam sent to > >> 550-5.7.1 Gmail, this message has been blocked. Please visit 550-5.7.1 > >> https://support.google.com/mail/?p=UnsolicitedMessageError 550 5.7.1 for > >> more information. o74si4960796qkl.67 - gsmtp (in reply to end of DATA > >> command)) > > > > Was your mail really sent from 2607:f308:1:1::212? According to DNS, > > your primary MX is bear.techie.net, with IP addresses 205.134.185.202 > > and 2607:f308:1:1::2. > > > > If may be worthwhile to fix the SMTP client IP address with > > "smtp_bind_address6 = 2607:f308:1:1::2", at least for off-site > > email. > > No, it's sent from 2607:f308:1:1::2. I don't know what the extra spaces + > 12 after the IP address mean in that error report from gmail.
How do you know? Did you record the packets? I know that your primary MX service is not reachable on 2607:f308:1:1::2, but it is reachable on 205.134.185.202. % telnet 2607:f308:1:1::2 smtp Trying 2607:f308:1:1::2... ^C % telnet 205.134.185.202 smtp Trying 205.134.185.202... Connected to bear.techie.net. Escape character is '^]'. 220 bear.techie.net ESMTP Postfix (Ubuntu) quit 221 2.0.0 Bye This would not be the first time that some IPv6 stack grabs an unexpected IPv6 address. Wietse