Here is how my server is configured:
linux1 = NAT Firewall
zimbra = Zimbra Server
linux1 uses iptables to forward following ports:
25 -> zimbra:25
8080 -> zimbra:80
2222 -> zimbra:22
linux1 runs it's own webserver (apache2) on port 80.
192.168.11.3 is zimbra server IP address. I have masked linux1 server's external IP address with x.x.x.x for privacy.
root@linux1 # iptables -t nat -L -n
Chain PREROUTING (policy ACCEPT)
target prot opt source destination
DNAT tcp -- anywhere X.X.X.X tcp dpt:8080 to:192.168.11.3:80
DNAT tcp -- anywhere X.X.X.X tcp dpt:25 to:192.168.11.3:25
DNAT tcp -- anywhere X.X.X.X tcp dpt:2222 to:192.168.11.3:22
Zimbra is working fine when accessed from LAN as zimbra.lan. However I am unable to access Zimbra server from outside.
With the port 8080 on linux1 (which is also visible as mydomain.com from internet) being forwarded to port 80 on zimbra, I was expecting that visiting http://mydomain.com:8080 from outside network, would enable me to access the web mail. As expected the login page shows correctly, but after I enter userid/password, it shows
"An unexpected error has occurred. Please correct any errors and retry. If the problem persists please contact your System Administrator. (service.FAILURE)"
Can you please help?