ISPConfig network IP address settings - public or local?

Which IP address I should have on ISPConfig setings
System / Server Config / Server / IP address

Should it be my public-IP (from ISP) or my internal-IP (static inhouse-IP like 192.168.xx.yyy)?
(In my case Server1 is behind ADSL-modem (as DMZ as seems to be well protected by perfect server instructions )

All seems to be working fine, but just to get it right, please let me know.

 

Hi Sir what do I fill in the following options within the ISPconfig >Server Settings.
Suppose my ISPconfig subdomain is "Server1.example.com"

• Hostname: The default value is „www“.
• Domain: The domain under which the ISPConfig system can be reached.
• Enter the netmask of your server.
• Admin Email: The email address of the person that should get a message from the ISPConfig system if one of the services on the server (e.g. web server) fails.

Do I enter my personal Gmail or should I enter the email that I used in configuring the ISPconfig?
Please help me

 

You should not revive 11 year old threads. Besides, this thread is about server IP-address, so your query about e-mail address is not related.
Where is this "Server Settings" in ISPConfig Panel?
Create a new thread and included more info. Maybe start with this:
https://www.howtoforge.com/community/threads/please-read-before-posting.58408/