Is this possible using SLES as a router/firewall? I know it works with
some commercial firewalls. SonicWALL is one of them.

Example:

Firewall/router (sLES)
Public interface: 10.0.23.100
Private interface: 192.168.24.1

Email Server
Interface: 192.168.24.2

Laptop/tablet/smart phone
Interface: local IP 192.168.24.3

Firewall configuration port forwarding:
10.0.23.100:25 --> 192.168.24.2:25

From the Internet I can access the email server using 10.0.23.100:25.
From the LAN I can access the email server using 192.168.24.2:25.

From the *LAN* I *want* to access the email server using 10.0.23.100:25
so that the device configuration doesn't have to be changed for
onsite/offsite access. I know I can accomplish this by setting up
appropriate internal/external DNS entries but that is not what I am
asking.

Any ideas?

--
Kevin Boyle - Knowledge Partner
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