Unable to access my local server from outside the domain

Question

I would really appreciate it if you could help me with this.

Im setting up an internal mail server using Zimbra server 8.0.3 and i want people from outside the domain to be able to access this server which is located locally.

I have a public ip provided by my ISP and i have assigned that IP to one port of the router(Where the link from the ISP comes in) and this server is located behind that Cisco Router with a public IP 192.168.xxx.xxx.

In that router i performed Nat Port Forwarding as seen below so that mail requests from outside will be forwarded to that server.

ip nat inside source list 10 interface GigabitEthernet0/1 overload
ip nat inside source static tcp 192.168.30.254 22 41.59.xx.xx 22 extendable
ip nat inside source static udp 192.168.30.254 22 41.59.xx.xx 22 extendable
ip nat inside source static tcp 192.168.30.254 25 41.59.xx.xx 25 extendable
ip nat inside source static tcp 192.168.30.254 80 41.59.xx.xx 80 extendable
ip nat inside source static tcp 192.168.30.254 110 41.59.xx.xx 110 extendable
ip nat inside source static tcp 192.168.30.254 143 41.59.xx.xx 143 extendable
ip nat inside source static tcp 192.168.30.254 389 41.59.xx.xx 389 extendable
ip nat inside source static udp 192.168.30.254 389 41.59.xx.xx 389 extendable
ip nat inside source static tcp 192.168.30.254 443 41.59.xx.xx 443 extendable
ip nat inside source static tcp 192.168.30.254 993 41.59.xx.xx 993 extendable
ip nat inside source static tcp 192.168.30.254 995 41.59.xx.xx 995 extendable
ip nat inside source static tcp 192.168.30.254 7025 41.59.xx.xx 7025 extendable

After that i change MX and A records of my internet domain mail.example.co.tz to point to that public ip 41.59.xx.xx so that any one accessing that link will be redirected to the public ip and then port forwarded to the mail server.

So here comes the problem...after all that when i access mail.example.co.tz opn a web browser it says Unable To connect.

Am i going wrong somewhere??

Answer 1

The Zimbra wiki lists ports 465 and 587, which you do not have forwarded. (It also marks 7025 as internal.)

Otherwise, please check each step of the connection:

1. Run nslookup mail.example.co.tz, and confirm that the domain is forwarded to the right public IP.

2. Run dig mail.example.co.tz, and confirm that your MX and A DNS records are sending mail to the right place. (You may need to configure records for example.co.tz, instead.)

3. If both of those are correct, use telnet to try and connect to a mail port. telnet mail.example.co.tz 22 should get some kind of response from the server. Try some of the other ports, too.