Static Routing - Routing Protocols and Concepts - page 73

Configuring and Verifying Interfaces Exercise

In this exercise, you will review the basic interface configuration for the HQ router shown earlier in
Figure 2-1.

HQ does not yet have any routes. You should add two routes by configuring the Fast Ethernet inter-
faces for HQ. By default, all router interfaces are shut down , or turned off. To enable this interface,
use the no shutdown command, which changes the interface from administratively down to up.

What commands will configure the Fast Ethernet interfaces with IP addresses and activate the
interfaces?
HQ(config)# interface fastethernet 0/0
HQ(config-if)# ip address 172.16.0.1 255.255.0.0
HQ(config-if)# no shutdown
UPDOWN: Interface FastEthernet0/0, changed state to up
*Mar 1 01:16:09.214: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0,
changed state to up
HQ(config-if)# interface fastethernet 0/1
HQ(config-if)# ip address 172.17.0.1 255.255.0.0
HQ(config-if)# no shutdown
UPDOWN: Interface FastEthernet0/1, changed state to up
*Mar 1 01:16:09.214: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0,
changed state to up

The IOS sends two messages to the console after you activate the interface. Both of these messages
are important. The first changed state to up message indicates that the physical layer is up. If you do
not get this first message, be sure that the interface is properly connected to a switch or a hub .

The second changed state to up message indicates that the data link layer is operational.

The IOS often sends unsolicited messages to the console while you are typing a command. To keep
the unsolicited output separate from your input, enter line configuration mode for the console port and
add the logging synchronous command.

After an interface is configured, it can be verified using various commands.

The show interfaces fastethernet 0/0 command shows that the Fast Ethernet interface is up and the
line protocol is up. The no shutdown command changed the interface from administratively down and
down to up and up. This command also shows the MAC address for the interface:
FastEthernet0/0 is up, line protocol is up
Hardware is AmdFE, address is 000c.3010.9260 (bia 000c.3010.9260)
Internet address is 172.16.0.1/24
<output omitted>

The show ip interface brief command also verifies that an interface is up and up:
Interface

IP-Address OK? Method Status Protocol

FastEthernet0/0 172.16.0.1 YES manual up up

Serial0/0/0 unassigned YES unset administratively down down

FastEthernet0/1 72.17.0.1 YES unset up up