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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter 22 Configuring IP Unicast Routing
Configuring IP Addressing
Configuring IP Addressing
A required task for configuring IP routing is to assign IP addresses to Layer 3 network interfaces to
enable the interfaces and allow communication with the hosts on those interfaces that use IP. These
sections describe how to configure various IP addressing features. Assigning IP addresses to the
interface is required; the other procedures are optional.
• Default Addressing Configuration, page 22-4
• Assigning IP Addresses to Network Interfaces, page 22-5
• Configuring Address Resolution Methods, page 22-10
• Routing Assistance When IP Routing is Disabled, page 22-14
• Configuring Broadcast Packet Handling, page 22-17
• Monitoring and Maintaining IP Addressing, page 22-21
Default Addressing Configuration
Table 22-1 shows the default addressing configuration.
Table 22-1 Default Addressing Configuration
Feature Default Setting
IP address None defined.
ARP No permanent entries in the Address Resolution Protocol (ARP) cache.
Encapsulation: Standard Ethernet-style ARP.
Timeout: 14400 seconds (4 hours).
IP broadcast address 255.255.255.255 (all ones).
IP classless routing Enabled.
IP default gateway Disabled.
IP directed broadcast Disabled (all IP directed broadcasts are dropped).
IP domain Domain list: No domain names defined.
Domain lookup: Enabled.
Domain name: Enabled.
IP forward-protocol If a helper address is defined or User Datagram Protocol (UDP) flooding is
configured, UDP forwarding is enabled on default ports.
Any-local-broadcast: Disabled.
Spanning Tree Protocol (STP): Disabled.
Turbo-flood: Disabled.
IP helper address Disabled.
IP host Disabled.
