54CHAPTER 4: PROBLEM SOLVING
enough power subsequently becomes available the port will be powered.
■Check that the port has not had a power limit imposed upon it.
Solving
Communication
Problems
If you experience communication problems with the Switch, ensure that:
■The Switch IP address 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 Supervisor).
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.