ELSA LANCOM Business 6000, Руководство пользователя

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Operating modes and functions
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ELSA LANCOM Business 6000
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of the computers in its own network that were assigned IP addresses via
DHCP. With the dynamic address assignments of a DHCP server, an
external DNS server might have difficulties in keeping the associations
between the names and IP addresses current.
When routing Windows networks via NetBIOS, the ELSA LANCOM
Business also knows the computer names and IP addresses in the other
connected NetBIOS networks. In addition, computers with fixed IP
addresses can also enter themselves in the NetBIOS table and thus be
known by their names and addresses.
The DNS server in the ELSA LANCOM Business can also be used as an
extremely convenient filter mechanism. Requests for domains can be
prohibited throughout the LAN, for subnetworks, or even for individual
computers—simply by specifying the domain name.
When processing requests for specific names, the DNS server takes
advantage of all of the information available to it:
First, the DNS server checks whether access to the name is not prohibited
by the filter list. If that is the case, an error message is returned to the
requesting computer stating that access to the address has been denied.
Next, it searches in its own static DNS table for suitable entries.
If the address cannot be found in the DNS table, it searches the dynamic
DHCP table. The use of DHCP information can be disabled if required.
If no information on the name can be located in the previous tables, the
DNS server then searches the lists of the NetBIOS module. The use of the
NetBIOS information can also be disabled if necessary.
If the requested name cannot be found in any of the information sources
available to it, the DNS server sends the request to another server—that of
the Internet provider, for example—using the normal DNS forwarding
mechanism, or returns an error message to the requesting computer.
6.5.2 Setting up the DNS server
The settings for the DNS server can be found in ELSA LANconfig in the
'TCP/IP' configuration section on the 'DNS Server' tab. To set up the DNS
server, proceed as follows:
햲
Switch the DNS server on.
set Setup/DNS-Module/Operating on