I disabled IPv6 in CentOS but connect with localhost not affected. Sent from Yahoo Mail on Android On Mon, Oct 12, 2020 at 6:48 PM, Jason Long<hack3r...@yahoo.com> wrote: # ifconfig
lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:80230 errors:0 dropped:0 overruns:0 frame:0 TX packets:80230 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:13792298 (13.1 MiB) TX bytes:13792298 (13.1 MiB) You right. # telnet 127.0.0.1 25 Trying 127.0.0.1... Connected to 127.0.0.1. Escape character is '^]'. 220 mail.example.net ESMTP Postfix ehlo 127.0.0.1 250-mail.example.net 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN Which lines of configuration must be change? On Monday, October 12, 2020, 06:38:42 PM GMT+3:30, IL Ka <kazakevichi...@gmail.com> wrote: " ::1" is a local address for IPv6 "127.[something]" is a local address of IPv4. https://en.wikipedia.org/wiki/Localhost My guess is that you didn't include IPv6 address to the list of "mynetworks", so Postfix can't "trust" it, because "smtpd_relay_restrictions" is default to: "permit_mynetworks, permit_sasl_authenticated, defer_unauth_destination", which means it only relays emails either from "mynetworks" or authenticated users. "localhost" is resolved to the IPv6 address on CentOS. You can explicitly disable IPv6: https://www.tecmint.com/disable-ipv6-in-centos-8/ Or use IPv4 address explicitly: "telnet 127.0.0.1 25". I'd stay with the latter case. On Mon, Oct 12, 2020 at 5:55 PM Jason Long <hack3r...@yahoo.com> wrote: > Thank you for your reply. > How can I sure I'm using IPv4 or IPv6? > > > On Monday, October 12, 2020, 06:18:10 PM GMT+3:30, IL Ka > <kazakevichi...@gmail.com> wrote: > >> mynetworks = 127.0.0.0/8, My Public IP >> Trying ::1... > It could be that you are using IPv6 to connect while "mynetworks" is IPv4 > address. > Try "telnet 127.0.0.1 25" >
