Jul 27 20:17:53 web1 postfix/pickup[1819]: A94A6140F9B: uid=48 from=<info@example.com>
Jul 27 20:17:53 web1 postfix/cleanup[2043]: A94A6140F9B: message-id=<20160727111753.A94A6140F9B@example.com>
Jul 27 20:17:53 web1 postfix/qmgr[1226]: A94A6140F9B: from=<info@example.com>, size=1094, nrcpt=1 (queue active)
Jul 27 20:17:54 web1 postfix/smtp[2045]: connect to smtp.gmail.com[2404:6800:4008:c03::6d]:587: Network is unreachable
Jul 27 20:17:58 web1 postfix/smtp[2045]: A94A6140F9B: to=<dodinhdoi@gmail.com>, relay=smtp.gmail.com[173.194.72.108]:587, delay=4.5, delays=0.32/0.13/2.2/1.9, dsn=2.0.0, status=sent (250 2.0.0 OK 1469618277 uc1sm8434082pac.24 - gsmtp)
Jul 27 20:17:58 web1 postfix/qmgr[1226]: A94A6140F9B: removed