3Com Traffix Transcend Traffix Manager, User Manual

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H
DHCP
This appendix contains the following sections:
■
How Traffix Manager Monitors DHCP Devices
■
What Effect Do DHCP Devices Have On The Map?
How Traffix
Manager Monitors
DHCP Devices
Traffix ™ Manager normally uses the Network Layer Address (for example,
IP address, IPX address) as the unique way to identify objects on your
network. However, the IP address of devices managed using the Dynamic
Host Control Protocol (DHCP) can change, and therefore this is an
unreliable method of identification for these devices.
The only certain way of identifying such devices in the Map is to use the
MAC address of the device. You can use the DHCP configuration file to
specify which devices you want Traffix Manager to identify using this
method. You can open this file by clicking
DHCP Setup in the Traffix
Control Panel.
What Effect Do
DHCP Devices Have
On The Map?
If a device which is managed using DHCP is discovered on your network,
it may appear on the Traffix Manager Map as a normal device until Traffix
Manager realizes it is a DHCP device.
A DHCP device requests an IP address from the DHCP server. DHCP is a
dynamic protocol, and the DHCP server can provide a different IP address
for the same device each time this request is made. If, according to your
local DHCP policy, the IP address of a device changes, the device will
appear exactly the same in the Map, except that its IP address will
change.
If the old IP address of a device is assigned to a new MAC address, a new
device is created in the Map. This new device will have the old IP address
and the new MAC address attribute assigned to it. The original device