3com 4226T User Manual

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C
HAPTER
 4: P
ROBLEM
 S
OLVING
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
If your IP network is internal to your organization only, that is, you do not 
access the Internet, you may use any arbitrary IP address as long as it is 
not being used by another device on your network. 3Com suggests you 
use addresses in the series 192.160.100.X (where X is a number between 
1 and 254) with a subnet mask of 255.255.255.0.
These suggested IP addresses are part of a group of IP addresses that 
have been set aside specially for use ‘in house’ only.
Solving Stack 
Formation 
Problems
If you are having problems with correctly forming a stack, first ensure that 
Spanning Tree is enabled. If it is enabled, do the following:
Power off all units in the stack.
Check all the cable connections in the stack.
Power on all units in the stack.
DUA1730-0AAA04.book  Page 56  Thursday, November 17, 2005  2:59 PM