
Gmail doesn't allow SMTP connections via IPv6 - phunehehe0
https://phunehehe.net/gmail-smtp-ipv6/
======
p1mrx
Your ISP is probably blocking SMTP-related ports inconsistently. Here's what I
see from Comcast Residential:

    
    
      $ nmap -6 -Pn 2404:6800:4003:c02::6c
      
      Starting Nmap 7.10 ( https://nmap.org ) at 2016-03-27 17:38 PDT
      Nmap scan report for sc-in-x6c.1e100.net (2404:6800:4003:c02::6c)
      Host is up (0.18s latency).
      Not shown: 996 filtered ports
      PORT    STATE SERVICE
      465/tcp open  smtps
      587/tcp open  submission
      993/tcp open  imaps
      995/tcp open  pop3s
      
      Nmap done: 1 IP address (1 host up) scanned in 13.51 seconds
      
      $ nmap -Pn 74.125.68.108
      
      Starting Nmap 7.10 ( https://nmap.org ) at 2016-03-27 17:38 PDT
      Nmap scan report for sc-in-f108.1e100.net (74.125.68.108)
      Host is up (0.19s latency).
      Not shown: 996 filtered ports
      PORT    STATE SERVICE
      465/tcp open  smtps
      587/tcp open  submission
      993/tcp open  imaps
      995/tcp open  pop3s
      
      Nmap done: 1 IP address (1 host up) scanned in 12.86 seconds

~~~
phunehehe0
I don't like the idea that Digital Ocean can be doing something that weird :)
But it seems like you are right. I'll drop them a note.

    
    
        $ mtr --report-wide 2404:6800:4003:c02::6c --tcp --port 993
        Start: Mon Mar 28 03:23:08 2016
        HOST: phunehehe-do3                      Loss%   Snt   Last   Avg  Best  Wrst StDev
          1.|-- 2400:6180:0:d0:ffff:ffff:ffff:fff1  0.0%    10    0.7   1.1   0.3   6.5   1.9
          2.|-- 2400:6180::601                      0.0%    10    0.3   0.3   0.3   0.4   0.0
          3.|-- 2400:6180::301                      0.0%    10    0.9   0.6   0.3   1.3   0.0
          4.|-- 2001:4860:1:1:2:82d::               0.0%    10    0.9   1.8   0.9   3.8   0.7
          5.|-- 2001:4860::1:0:518d                 0.0%    10    1.7   2.0   1.7   2.2   0.0
          6.|-- 2001:4860::2:0:ab29                 0.0%    10    2.2   9.5   1.8  64.4  19.6
          7.|-- 2001:4860::2:0:ab28                40.0%    10    2.7   2.4   1.7   3.3   0.4
          8.|-- sc-in-x6c.1e100.net                70.0%    10  127.0 151.6 126.9 200.8  42.6
    
        $ mtr --report-wide 2404:6800:4003:c02::6c --tcp --port 465
        Start: Mon Mar 28 03:23:30 2016
        HOST: phunehehe-do3 Loss%   Snt   Last   Avg  Best  Wrst StDev

~~~
p1mrx
Sounds like this, then:

[https://warrenguy.me/blog/ipv6-digital-ocean-
crippled](https://warrenguy.me/blog/ipv6-digital-ocean-crippled)

~~~
phunehehe0
You are exactly right. Thanks again.

