Cisco Systems 78-11741-02 Icmp Services Example, Simplex Ethernet Interfaces Example, IPC-121

Configuring IP Services

IP Services Configuration Examples

•Time Range Applied to an IP Access List Example

•Commented IP Access List Entry Examples

•IP Accounting Example

•HSRP Load Sharing Example

•HSRP MAC Refresh Interval Examples

•HSRP MIB Trap Example

•HSRP Support for MPLS VPNs Example

•HSRP Support for ICMP Redirect Messages Example

•MNLB Forwarding Agent Examples

ICMP Services Example

The following example changes some of the ICMP defaults for the first Ethernet interface 0. Disabling the sending of redirects could mean that you do not expect your devices on this segment to ever need to send a redirect message. Disabling the unreachables messages will have a secondary effect—it also will disable IP Path MTU Discovery, because path discovery works by having the Cisco IOS software send Unreachables messages. If you have a network segment with a small number of devices and an absolutely reliable traffic pattern—which could easily happen on a segment with a small number of little-used user devices—you would be disabling options that your device would be unlikely to use anyway.

interface ethernet 0

no ip unreachables no ip redirects

Simplex Ethernet Interfaces Example

The following is an example of configuring a simplex Ethernet interface. Figure 19 illustrates how to configure IP on two routers sharing transmit-only and receive-only Ethernet connections.

Figure 19 Simplex Ethernet Connections

	E0	E0
	E1	E1
Router 1			Router 2

S1064a

Router 1 Configuration

interface ethernet 0 ip address 128.9.1.1

!

interface ethernet 1 ip address 128.9.1.1 transmit-interface ethernet 0

!

!use show interfaces command to find router2-MAC-address-E0 arp 128.9.1.4 router2-MAC-address-E0 arpa

Router 2 Configuration

interface ethernet 0

Cisco IOS IP Configuration Guide

IPC-121