Hi to all, this is my first thread.
I’m not very good in all this things (I’m not very good in English, too)
I have a problem – I don’t know what is my pop3 server address! And I don’t know how to figured out (this is my first question).
Situation: I have suse 9.3 server, postfix and courier. Everything works inside LAN, I use 192.168.1.1 as pop3 address for the clients (and SMTP too). Outside LAN my pop3 doesn’t work (except webmail).
Now I need to configure my pop3 server to have outside address pop3.server.com.
(this address is written in my providers DNS tables).
Thank you!

Without knowing how your network is set up, that's pretty hard to answer.

I'd hesitate a guess though, that if you have an MX record set up with your DNS to point to your postfix server, it's probably the same external IP (if the pop server and postfix server are the same machine).

From there you will need to make sure that the pop3 ports (110 and 995 for pops) are open on your firewall and forwarded to the correct machine on your LAN. Again, I think you'll find this is similar to what you are probably doing with port 25 for smtp on postfix.

Thanks for answer!
Everything is on the one machine, I have only one server.
In

/etc/sysconfig/named
/ets/named.conf
/var/lib/named

I don/t have any MX record.
I wrote next two lines in my firewall.sh:

$I –A INPUT –p tcp –I provider1 –dport 110 –syn –j ACCEPT
$I –A INPUT –p tcp –I provider2 –dport 110 –syn –j ACCEPT

I have tried to use server public ip address, but it doesn’t work, too.
(and it’s not SMTP server, it’s IMAP, sorry)

I put in the reference to smtp in case you had that working and you could have just followed the same process, but clearly that won't work in your case.

I don't follow you iptables rule - what is the -I provider1 (or 2) meant to be for?

That said, what is your setup? Do you have a router between your server and the internet, or a gateway/firewall, etc? If so, you need to ensure that it's forwarding pop requests to the server.

You should also make sure that you use TLS with pop (it may still be port 110, but I'm not certain) or pops on port 995. You really don't want plain test passwords being sent around unencrypted.

Uff, my fault... This is the lines in my firewall. Provider1 is my first ISP and provider2 is my second ISP.
Everything works now, I made mistake in second line
I type extra space, and line was not functional...
Really thank you for answers billymayday!
Only port 110 was problem...