GlobalSCAPE DMZ Gateway v3.1, User Manual

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DMZ Gateway User Guide
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In the DMZ Gateway administration interface, you can start and stop the service from the Server menu or
using the toolbar controls.
Specifying the Listening IP Addresses
For each DMZ Gateway Profile, you specify 2 IP addresses:
1. One address is used by client programs to connect. This is typically an external-facing address.
When a Site configured at a peer server connects to the DMZ Gateway over the PNC, the DMZ
Gateway reads the list of client ports configured in the Site. These ports are then combined with
the client IP Address and it is on these client IP address/Site port combinations that the DMZ
Gateway will listen for client connections.
2. The other address specifies the IP address on which to listen for connections from peer servers.
The communications established using this address is known as the Peer Notification Channel or
PNC . Typically this IP Address will be an internal-facing address. This address is combined with
the configured port value and it is on this IP Address/port combination that the DMZ Gateway will
listen for connections from peer servers.
Each address is configured by selecting the IP address to use from a drop-down list in the Profile
Configuration . The list of IP address includes all IPv4 addresses present on the computer. Additionally,
the list includes an All Available setting.
IMPORTANT:
All Available means that DMZ Gateway will listen on the IP address/port combination ONLY IF
that IP address/port combination is not already being used by another Profile. Profiles configured
with an explicit IP address have precedence over Profiles configured with
All Available .
What Does This Mean for the Peer Server Listeners?
Suppose you have 3 IP addresses on the computer: IP 1, IP 2, and IP 3, and you have 2 Profiles: Profile
1 and Profile 2.

Both Profiles are configured to use the same Peer Server Listener Port 54321.

Profile 1 is set to use All Available .

Profile 2 is set to use IP 2.
Profile 1 will listen on IP 1:54321 and IP 3:54321 , and Profile 2 will listen on IP 2:54321 .
Now, suppose you delete Profile 2, making IP 2:54321 available. The DMZ Gateway will detect this and
update the communications listeners so that Profile 1 will now listen on IP 1:54321 , IP 2:54321 , and IP
3:54321 .
What Does This Mean for the Client Listeners?
Suppose you have 3 IP addresses on the computer: IP 1, IP 2, and IP 3, and you have 2 Profiles: Profile
1 and Profile 2. Profile 1 is set to use
All Available and Profile 2 is set to use IP 2.
Now suppose you have 2 Sites configured on EFT Server. Both Sites are configured to connect to the
DMZ Gateway and use FTP port 21. Site 1 is set to connect to Profile 1, and Site 2 is set to connect to
Profile 2.
Once both Sites are connected, the DMZ Gateway will establish client listeners for Site 1 on IP 1:21 and
IP 3:21 (because Site 1 used Profile 1, which uses all available IP/port combinations not currently in use).
For Site 2 the DMZ Gateway will establish a client listener on IP 2:21 .