3Com 3CR17251-91 - Switch 5500G-EI Stackable Gigabit..., Getting Started Manual

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Solving Communication Problems 81
Solving
Communication
Problems
If you experience communication problems with the Switch, ensure that:
■
The Switch IP address and Management VLAN ID has been configured
as described in
Chapter 3 .
■
If the Switch is separated from your management application by a
router, ensure that the default gateway IP address within the Switch is
the same as the IP address of the router.
■
The Switch’s IP address has been entered correctly in your network
management application (such as 3Com Network Director).
The following is a brief overview of IP addressing, and how to obtain a
registered IP address.
IP Addressing
To be managed correctly, each device on your network (for example a
Switch or Hub) must have a unique IP address. IP addresses have the
format
n.n.n.n where n is a decimal number between 0 and 255. An
example IP address is 192.168.100.8.
The IP address is split into two parts:
■
The first part (‘192.168.100’ in the example) identifies the network on
which the device resides
■
The second part (‘.8’ in the example) identifies the device within the
network
The natural subnet mask for this example is 255.255.255.0.
If your network has a connection to the external IP network, that is, you
access the Internet, you must apply for a registered IP address.
How do you obtain a registered IP Address?
The IP registration system ensures that every IP address used is unique; if
you do not have a registered IP address, you may be using an identical
address to someone else and your network will not operate correctly.
InterNIC Registration Services is the organization responsible for
supplying registered IP addresses. The following contact information is
correct at time of publication:
World Wide Web site:
http://www.internic.net