Reference Guide

IPv4 Routing

IPv4 routing is supported on the S4820T platform.

FTOS supports various IP addressing features. This chapter describes the basics of domain name service (DNS),

address resolution protocol (ARP), and routing principles and their implementation in the Dell Networking operating

system (FTOS).

IP Feature Default

DNS Disabled

Directed Broadcast Disabled

Proxy ARP Enabled

ICMP Unreachable Disabled

ICMP Redirect Disabled

IP Addresses

FTOS supports IP version 4, as described in RFC 791. FTOS also supports classful routing and variable length subnet

masks (VLSM).

With VLSM, you can configure one network with different masks. Supernetting, which increases the number of subnets,

is also supported. To subnet, you add a mask to the IP address to separate the network and host portions of the IP

address.

At its most basic level, an IP address is 32-bits composed of network and host portions and represented in dotted

decimal format. For example, 00001010110101100101011110000011 is represented as 10.214.87.131.

For more information about IP addressing, refer to RFC 791, Internet Protocol.

Implementation Information

In FTOS, you can configure any IP address as a static route except IP addresses already assigned to interfaces.

NOTE: FTOS versions 7.7.1.0 and later support 31-bit subnet masks (/31, or 255.255.255.254) as defined by RFC 3021.

This feature allows you to save two more IP addresses on point-to-point links than 30-bit masks. FTOS supports

RFC 3021 with ARP.

Configuration Tasks for IP Addresses

The following describes the tasks associated with IP address configuration.

Configuration tasks for IP addresses includes:

• Assigning IP Addresses to an Interface (mandatory)

• Configuring Static Routes (optional)

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