IP Routing Features

Configuring IP Parameters for Routing Switches

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Configuring IP Parameters for Routing Switches

The following sections describe how to configure IP parameters. Some param­ eters can be configured globally while others can be configured on individual VLAN interfaces. Some parameters can be configured globally and overridden for individual VLAN interfaces.

This section describes how to configure IP parameters for routing switches. For IP configuration information when routing is not enabled, refer to the chapter on IP addressing in the Management and Configuration Guide.

Configuring IP Addresses

You can configure an IP address on the routing switch’s VLAN interfaces. Configuring IP addresses is described in detail in the chapter on IP addressing in the Management and Configuration Guide.

Configuring ARP Parameters

Address Resolution Protocol (ARP) is a standard IP protocol that enables an IP routing switch to obtain the MAC address of another device’s interface when the routing switch knows the IP address of the interface. ARP is enabled by default and cannot be disabled.

How ARP Works

A routing switch needs to know a destination’s MAC address when forwarding traffic, because the routing switch encapsulates the IP packet in a Layer 2 packet (MAC layer packet) and sends the Layer 2 packet to a MAC interface on a device directly attached to the routing switch. The device can be the packet’s final destination or the next-hop router toward the destination.

The routing switch encapsulates IP packets in Layer 2 packets regardless of whether the ultimate destination is locally attached or is multiple router hops away. Since the routing switch’s IP route table and IP forwarding cache contain IP address information but not MAC address information, the routing switch cannot forward IP packets based solely on the information in the route

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