Outgoing connections on port 25 / 587 / 143 blocked over IPv6?
I just moved my servers, including my mailserver to the new ams3 region because of ipv6. i configured postfix to use ipv6 and i recieved my first email over ipv6 without a problem.
But when i try to send mail over ipv6 to other mailserver that support ipv6 like gmail.com the connection times out.
I then used netcat to test it and found that three mail relevant ports seem to be blocked for outgoing connections. SSH works fine.
nc -vz [ipv6-address] 25 nc: connect to [ipv6-address] port 25 (tcp) failed: Connection timed out nc -vz [ipv6-address] 587 nc: connect to [ipv6-address] port 587 (tcp) failed: Connection timed out nc -vz [ipv6-address] 143 nc: connect to [ipv6-address] port 143 (tcp) failed: Connection timed out nc -vz [ipv6-address] 22 Connection to [ipv6-address] 22 port [tcp/ssh] succeeded
Are these ports really blocked? If yes, why?
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