Product guide

IP Routing Features
Contents
Overview of OSPF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-34
Configuring OSPF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-38
Displaying OSPF Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-53
OSPF Equal-Cost Multipath (ECMP) for Different
Subnets Available Through the Same Next-Hop Routes . . . . . . . . . 11-70
Enabling IRDP Globally . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-74
Enabling IRDP on an Individual VLAN Interface . . . . . . . . . . . . . . . 11-74
Displaying IRDP Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-75
Configuring DHCP Relay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-76
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-76
DHCP Option 82 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-76
DHCP Packet Forwarding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-91
Minimum Requirements for DHCP Relay Operation . . . . . . . . . . . . 11-91
Enabling DHCP Relay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-91
Configuring a Helper Address . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-92
Viewing the Current DHCP Relay Configuration . . . . . . . . . . . . 11-92
UDP Broadcast Forwarding on 5300xl,
4200vl and 3400cl Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-97
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-97
Subnet Masking for UDP Forwarding Addresses . . . . . . . . . . . . . . . 11-98
Configuring and Enabling UDP Broadcast Forwarding . . . . . . . . . . 11-99
Displaying the Current IP Forward-Protocol Configuration . . . . . 11-101
Operating Notes for UDP Broadcast Forwarding . . . . . . . . . . . . . . 11-102
Messages Related to UDP Broadcast Forwarding . . . . . . . . . . . . . 11-102
Configuring Static Network Address
Translation (NAT) for Intranet
Applications on the 5300xl Switches . . . . . . . . . . . . . . . . . . . . . . . . 11-103
Static NAT Operating Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-104
Configuring Static NAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-104
Displaying Static NAT Statistics and Configuration . . . . . . . . . . . . 11-106
Static NAT Operating Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-106
11-2