72 CHAPTER 9: USING AUTOMATIC IP CONFIGURATION
How Your Switch 
Obtains IP 
Information 
Your Switch has two ways to obtain its IP address information:
■ Automatic IP Configuration (default) — the Switch attempts to 
configure itself by communicating with a DHCP server on the 
network.
■ Manual IP Configuration — you can manually input the IP 
information (IP address, subnet mask, and default gateway).
If you select an option for no IP configuration the Switch will not be 
accessible from a remote management workstation on the LAN. In 
addition, the Switch will not be able to respond to SNMP requests. 
How Automatic IP 
Configuration 
Works
When your Switch is powered up for the first time the IP configuration 
setting is set to auto — this is the default setting.
If your Switch has been powered up before, whichever of the three 
options for IP configuration (manual, auto, none) was last 
configured is activated when the Switch powers up again. 
You can switch to manual IP configuration at any time using a serial port 
connection to set up the IP information. For more information see the 
Getting Started Guide that accompanies your Switch.
Automatic Process To detect its IP information using the automatic configuration process, 
the Switch continually attempt to contact a DHCP server on the network 
requesting IP information from the server.
If a DHCP server is on the network and working correctly it responds to 
the clients request with an IP address (allocated from a pool of available 
addresses) and other parameters such as a subnet mask, default gateway, 
lease time, and any other options configured in the DHCP server.
The way a DCHP server responds is dependant on the DHCP server 
settings. Therefore the way your DHCP server responds may be different 
to the process outlined.
Important 
Considerations
This section contains some important points to note when using the 
automatic IP configuration feature.