User's Manual

170 CHAPTER 5: WORKING WITH THE MAP
between subnets and routers or layer-3 switches are shown as physical
links. For more information see “
Navigating Between Submaps and the
Top-Level Map” on page 184.
If a router or layer-3 switch in your network has two or more IP interfaces
configured on a single port then the subnets that those IP interfaces
belong to will be grouped together into a single submap. This helps
represent the fact that these subnets exist on the same physical LAN
segment. Such a configuration is sometimes known as "one-armed
routing".
In such a case the submap will contain the devices in all associated IP
subnets. The subnet icon’s name will include all of the IP subnets that it
represents:
Figure 58 Subnet Icon’s Name
Undiscovered Subnets
If 3Com Network Director discovers a device that has an IP interface on a
subnet that 3Com Network Director has not recognized, then an
undiscovered subnet icon will be added to the top-level map and linked
to the device. Undiscovered subnet icons represent areas of the network
that have not yet been discovered by 3Com Network Director, and give
you a convenient way to visualize and progressively map your entire
network. Double-clicking on an undiscovered subnet allows you to
launch a Network Discovery operation against the IP subnets represented
by the Undiscovered subnet icon. For more information about network
discovery see “
Discovering the Network” on page 91.
If you do not wish to see the undiscovered subnets in your top-level map
then turn off the View
> Show Undiscovered Subnets option. This will
simplify the contents of your map by hiding all of the undiscovered
subnets. If you turn off this option then you may also wish to relayout
your map. For more information see “
Modifying the Map Layout” on
page 200
.