Configuring Static Dhcp - ZyXEL Communications ZyWall P1 User Manual

Table 18 LAN: LAN (continued)
LABEL
DNS Servers
Assigned by
DHCP Server
First DNS Server
Second DNS
Server
Third DNS Server
Windows
Networking
(NetBIOS over
TCP/IP)
Allow between
LAN and WAN
Apply
Reset

4.5 Configuring Static DHCP

This table allows you to assign one IP address on the LAN to a specific computer based on the
MAC address.
Every Ethernet device has a unique MAC (Media Access Control) address. The MAC address
is assigned at the factory and consists of six pairs of hexadecimal characters, for example,
00:A0:C5:00:00:02.
To change your ZyWALL's static DHCP settings, click LAN, then the Static DHCP tab. The
screen appears as shown.
Chapter 4 LAN Screens
DESCRIPTION
The ZyWALL passes a DNS (Domain Name System) server IP address (in the
order you specify here) to the DHCP client. The ZyWALL only passes this
information to the LAN DHCP client when you select the DHCP Server check box.
When you clear the DHCP Server check box, DHCP service is disabled and you
must have another DHCP sever on your LAN, or else the computers must have
their DNS server addresses manually configured.
Select From ISP if your ISP dynamically assigns DNS server information (and the
ZyWALL's WAN IP address). Use the drop-down list box to select a DNS server IP
address that the ISP assigns in the field to the right.
Select User-Defined if you have the IP address of a DNS server. Enter the DNS
server's IP address in the field to the right. If you chose User-Defined, but leave
the IP address set to 0.0.0.0, User-Defined changes to None after you click Apply.
If you set a second choice to User-Defined, and enter the same IP address, the
second User-Defined changes to None after you click Apply.
Select DNS Relay to have the ZyWALL act as a DNS proxy. The ZyWALL's LAN IP
address displays in the field to the right (read-only). The ZyWALL tells the DHCP
client on the LAN that the ZyWALL itself is the DNS server. When a computer on
the LAN sends a DNS query to the ZyWALL, the ZyWALL forwards the query to the
ZyWALL's system DNS server (configured in the DNS System screen) and relays
the response back to the computer. You can only select DNS Relay for one of the
three servers; if you select DNS Relay for a second or third DNS server, that choice
changes to None after you click Apply.
Select None if you do not want to configure DNS servers. If you do not configure a
DNS server, you must know the IP address of a computer in order to access it.
NetBIOS (Network Basic Input/Output System) are TCP or UDP packets that
enable a computer to connect to and communicate with a LAN. For some dial-up
services such as PPPoE or PPTP, NetBIOS packets cause unwanted calls.
However it may sometimes be necessary to allow NetBIOS packets to pass
through to the WAN in order to find a computer on the WAN.
Select this check box to forward NetBIOS packets from the LAN to the WAN and
from the WAN to the LAN. If your firewall is enabled with the default policy set to
block WAN to LAN traffic, you also need to enable the default WAN to LAN firewall
rule that forwards NetBIOS traffic.
Clear this check box to block all NetBIOS packets going from the LAN to the WAN
and from the WAN to the LAN.
Click Apply to save your changes back to the ZyWALL.
Click Reset to begin configuring this screen afresh.
ZyWALL P1 User's Guide
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