I am quite stuck with my postfix/smtp configuration on my CentOS machine.
I setup a mail dns mail.domain.tld, configured in the postfix main.conf file and tested locally on the server by connecting to
$telent mail.domain.tld 25
This gives me a response and it's possible to send e-mails from the mail server it self. Now, I want to use the mail server in my e-mail client but I cant get a connection with the server, if i test a telnet connection from my local desktop it's been refused by the server.
I know this should be something like a firewall, there is iptables running but I added ports to be accepted, I added + saved + restarted iptables but no port 25 or 587 (also configured from the postfix master.conf) wont work from outside the server.
(telnet 587 also not working from the server locally).
# lsof -ni tcp:25
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
master 27179 root 12u IPv4 52473467 0t0 TCP *:smtp (LISTEN)
master 27179 root 13u IPv6 52473469 0t0 TCP *:smtp (LISTEN)
# netstat -an | grep LIST
...
tcp 0 0 0.0.0.0:465 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN
...
# iptables -L
Chain INPUT (policy DROP)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere tcp dpt:smtp
I can deliver more outputs if needed!
Thanks in advance