Configuring with Web Based Management   
4.4 "System" menu 
  SCALANCE SC-600 Web Based Management (WBM) 
128  Configuration Manual, 10/2021, C79000-G8976-C475-03 
•  DNS Server Address 
Shows the IP address of the DNS server. 
•  Origin 
Shows whether the DNS server was configured manually or was assigned by DHCP. 
4.4.3.2  DNS proxy 
The device provides a DNS server for the local network. If you enter the IP address of the 
device in the local application as a DNS server, then the device answers the DNS 
requests from its cache.  
If the device does not know the IP address for a domain address, it forwards the query to 
an external DNS server. How long the device keeps a domain address in the cache 
depends on the host being addressed. In addition to the IP address, a DNS request to an 
external DNS server also supplies the life span of this information.  
 
Description 
The page contains the following boxes: 
•  Enable DNS Proxy 
Enable or disable the proxy of the DNS server.  
•  Cache Name Errors (NXDOMAIN) 
Enable or disable the caching of NXDOMAIN replies. If you enable the option, the 
domain names that were unknown to the DNS server remain in the cache.  
 
4.4.3.3  DDNS client 
The DDNS (Dynamic Domain Name System) is an Internet service that allows a fixed 
hostname to be set up as a pseudonym for a dynamically changing IP address.  
The DDNS client synchronizes the assigned IP address with the hostname registered at 
the DDNS provider. This means that the device can always be reached using the same 
hostname.