Cisco Catalyst 3750-X User Manual

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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 42 Configuring IP Unicast Routing
Configuring IP Addressing
Figure 42-3 No IP Classless Routing
To prevent the switch from forwarding packets destined for unrecognized subnets to the best supernet
route possible, you can disable classless routing behavior.
Beginning in privileged EXEC mode, follow these steps to disable classless routing:
To restore the default and have the switch forward packets destined for a subnet of a network with no
n
etwork default route to the best supernet route possible, use the ip classless global configuration
command.
Configuring Address Resolution Methods
You can control interface-specific handling of IP by using address resolution. A device using IP can have
both a local address or MAC address, which uniquely defines the device on its local segment or LAN,
and a network address, which identifies the network to which the device belongs.
Note In a switch stack, network communication uses a single MAC address and the IP address of the stack.
The local address or MAC address is known as a data link
address because it is contained in the data link
layer (Layer 2) section of the packet header and is read by data link (Layer 2) devices. To communicate
with a device on Ethernet, the software must learn the MAC address of the device. The process of
learning the MAC address from an IP address is called address resolution. The process of learning the
IP address from the MAC address is called reverse address resolution.
Host
128.20.1.0
128.20.2.0
128.20.3.0
128.20.4.1
128.0.0.0/8
128.20.4.1
Bit bucket
45748
128.20.0.0
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
no ip classless Disable classless routing behavior.
Step 3
end Return to privileged EXEC mode.
Step 4
show running-config Verify your entry.
Step 5
copy running-config startup-config (Optional) Save your entry in the configuration file.

Cisco Catalyst 3750-X Specifications

General

Switching Capacity	160 Gbps
Stacking Bandwidth	64 Gbps
Max Stacking Units	9
Layer Support	Layer 2 and Layer 3
Form Factor	Rack-mountable
DRAM	256 MB
Flash Memory	64 MB
Model	Cisco Catalyst 3750-X Series
Ports	24 or 48 10/100/1000 Ethernet ports
Uplink Interfaces	4 SFP or 2 SFP+
Features	StackWise Plus, EnergyWise
Image	IP Base or IP Services
Operating Temperature	0 to 40°C
Operating Humidity	10 to 85% noncondensing