Interface and Connection States
Lab 1.18: Verifying Your Configuration
2. You can ping with different protocols, and you can see this by typing ping ? at the router user mode or privileged mode prompt, but not configuration mode
Network Layout
Load the network layout you have been working with for labs in section 1.
Ping
A diagnostic program that sees if a specific IP address is accessible. Packets are sent to the specified location and if they return correctly, communication was successful. This is used to verify connection to a remote host. Ping works at layer 3 of the OSI model.
Lab 1.18: Verifying Your Configuration 83
2621A#ping ?
WORD Ping destination address or hostname clns CLNS echo
ip IP echo
tag Tag encapsulated IP echo
<cr>
This program only supports IP ping at this time.
3. You can also use the traceroute program to find the path a packet takes as it traverses an internetwork. Traceroute can also be used with multiple protocols.
2621A#traceroute ?
WORD Trace route to destination address or hostname appletalk AppleTalk Trace
This program only supports IP with the trace command.
4. Telnet can be used to test IP connectivity and to gain access into remote routers. Once you gain access into the remote router you can interact with the device as though you are physically in front of it. From the router prompt, you do not need to type the telnet command. If you just type a hostname or IP address, it will assume you want to telnet.
The following example shows how to use Telnet from a router prompt. However, you need to have a configured a working network and destination host for Telnet to be suc-cessful. We will use Telnet more in other labs.
2621A#telnet ?
WORD IP address or hostname of a remote system <cr>
Traceroute
A TCP/IP utility that allows a user to determine if two computers are communicating successfully with each other. This network tool is used to determine the route taken by packets across an IP network. The time and location of the route taken to reach its des-tination computer is displayed. Traceroute works at layer 3 of the OSI model.
5. Another way to verify your configuration is by typing show interface commands. The first command is show interface?, which shows us all the available configured or physical interfaces for a device. The only interfaces that are not logical are FastEthernet and Serial.
2621A#show int ?
Async Async interface
BVI Bridge-Group Virtual Interface CTunnel CTunnel interface
Dialer Dialer interface FastEthernet FastEthernet IEEE 802.3 Loopback Loopback interface Virtual-Template Virtual Template interface Virtual-TokenRing Virtual TokenRing
accounting Show interface accounting
crb Show interface routing/bridging info dampening Show interface dampening info description Show interface description
irb Show interface routing/bridging info mac-accounting Show interface MAC accounting info
mpls-exp Show interface MPLS experimental accounting info precedence Show interface precedence accounting info rate-limit Show interface rate-limit info
<cr>
6. You can be specific with the command and use show interface fastethernet 0/0, or serial 0/0.
2621A#show int fa0/0
FastEthernet0/0 is up, line protocol is up
Hardware is AmdFE, address is 00b0.af40.3e18 (bia 00b0.af40.3e18) Description: Sales Lan
Internet address is 172.16.10.2/24
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec, reliablility 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full -duplex, 100Mb/s, 100BaseTX/FX ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:50, output 00:00:04, output hang never
Lab 1.18: Verifying Your Configuration 85
Last clearing of "show interface" counters never Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops 5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 1000 bits/sec, 0 packets/sec 588 packets input, 74628 bytes
Received 588 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 0 watchdog, 0 multicast
0 input packets with dribble condition detected 231 packets output, 53712 bytes, 0 underruns 0 output errors, 0 collisions, 1 interface resets 0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
--More--[output cut]
7. Use the show controllers command to display information about the physical interface itself. It will also give you the type of serial cable plugged into a serial port. Typically this will only be a DTE cable, which then plugs into a type of Data Service Unit (DSU).
2621A#show controllers s 0/0 Interface Serial0/0
Hardware is PowerQUICC MPC860 DCE V.35, clock rate 64000
idb at 0x813CA7B4, driver data structure at 0x813D1CE8 [output cut]
8. Clear all configurations. You will want to clear the configurations for any router for which you have entered information, up to this point. This will allow you to configure the devices according to the suggested labs without any extraneous information.
2621A#erase startup-config
Erasing the nvram filesystem will remove all configuration files! Continue?
[con firm]enter [OK]
Erase of nvram: complete 2621A#
01:58:09: %SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram 2621A#reload
System configuration has been modified. Save? [yes/no]: no Proceed with reload? [confirm] enter
Would you like to enter the initial configuration dialog? [yes/no]: n
Lab 1.19: do Command
The do command allows you ping other devices and view configurations while in the global configuration mode. Before IOS version 12.3, you could not use the do command. You had to be in user or privileged mode in order to ping other devices or view configurations. However, beginning with IOS version 12.3 you can use the do command in the configuration mode to accomplish this. With IOS version 12.2 you can also use the do command if you have the IOS Special Edition (SE). The do command is convenient because you do not have to exit the cur-rent configuration mode and perform the command in the privileged mode.
With this program, there are three devices that will allow you to use the do command in global configuration mode:
N 2811 router
N
N 2960 switch
N 3560 switch
Network Layout
Load the network layout you have been working with for labs in section 1.
Lab 1.19: do Command 87
Lab Steps
1. On the Network Visualizer screen, double-click on 2811 Router A. This will bring up a console screen.
2. Press enter and the Router> prompt will appear. You are now in the user mode.
3. Change to the privileged mode.
Router>
Router>enable
4. Change to the Global Configuration mode. Perform the do show run command and the do show int s /0/0/0 command.
Router#
Router#config t
Router(config)#do show run Building configuration...
Current configuration : 3401 bytes
!
version 12.4
service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption
!
[output cut]
Router(config)#do show int s 0/0/0
Serial0/0/0 is administratively down, line protocol is down Hardware is GT96K Serial
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, reliablility 255/255, txload 1/255, rxload 1/255 Encapsulation HDLC, loopback not set
Keepalive set (10)
Last input 00:00:02, output 00:00:06, output hang never Last clearing of "show interface" counters 02:41:59
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops) Conversations 0/1/256 (active/max active/max total) Reserved Conversations 0/0 (allocated/max allocated) Available Bandwidth 1158 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec 1645 packets input, 100265 bytes, 0 no buffer
Received 1139 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 1662 packets output, 105842 bytes, 0 underruns
0 output errors, 0 collisions, 3 interface resets 0 output buffer failures, 0 output buffers swapped out 2 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
5. On the Network Visualizer screen, double-click on 3560 Switch A. This will bring up a console screen.
6. Press Enter and the Switch> prompt will appear. You are now in the user mode.
7. Change to the privileged mode.
Switch>
Switch>enable
8. Change to the global configuration mode. Perform the do show run command.
Switch#
Switch#config t
3560A(config)#do show run Building configuration...
Current configuration : 898 bytes
!
Lab 1.19: do Command 89
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
interface FastEthernet0/1 [output cut]
IP Routing
to IP Routing
This section will discuss the IP routing process. This is an important subject to understand as it pertains to all routers and configurations that use IP. IP routing is the process of moving packets from one network to another network and delivering the packets to hosts. This section will give you the background on how to configure and verify IP routing with Cisco routers.
The following labs are covered in this section:
N
N 2.1: Configuring the SDM for the 2811 Router
N
N 2.2: Connecting to the SDM using the 2811 Router
N
N 2.3: Configuring an Interface with SDM
N
N 2.4: Configuring DHCP with SDM
N
N 2.5: Configuring Other Items with SDM
N
N 2.6: Verifying Configurations with SDM
N
N 2.7: Configuring the Routers
N
N 2.8: Verifying the Configurations
N
N 2.9: Configuring Static Routing
N
N 2.10: Verifying Static Routing
N
N 2.11: Configuring and Verifying Hosts
N
N 2.12: Configuring Default Routing
N
N 2.13: Verifying Default Routing
N
N 2.17: Using Debug with a RIPv2 Network
N
N 2.18: Configure and Verify a Loopback Interface
N
N 2.19: Using ARP (Address Resolution Protocol)
Lab 2: Introduction to IP Routing 93
The following commands are used in this section:
Command Meaning
debug ip igrp events Provides a summary of the IGRP routing information running on the network
debug ip igrp transactions Shows message requests from neighbor routers asking for an update and the broadcasts sent from your router towards that neighbor router
debug ip rip Sends console messages displaying information about RIP packets being sent and received on a router interface
ip classless Global configuration command used to tell a router to forward packets to a default route when the destination network is not in the routing table
ip route Creates static and default routes on a router network Tells the routing protocol what network to advertise no auto-summarization Disables auto summarization
no ip route Removes a static or default route router eigrp as Turns on IP EIGRP routing on a router router igrp as Turns on IP IGRP routing on a router router rip Turns on IP RIP routing on a router
show ip protocols Shows the routing protocols and timers associated with each routing protocol configured on a router
show ip route Displays the IP routing table
show protocols Shows the routed protocols and network addresses configured on each interface
version 2 Enables rip version 2