04-03-2019 11:10 PM
Greetings,
Please forgive my absolute ignorance on the subject, as I am just starting out with my recently-bought home lab.
I have 3 routers (Cisco 1841s) and I am trying to connect them together and send a ping when consoled into router 1. I configured each of the IPs/subnets as per the instructions in this lesson I am following for static routing. As of now, I cannot get a response and I don't understand why. I am trying to ping 192.168.1.2 from Router 1 and get no reply.I am using a crossover cable to connect port fa0/0 of R1 to fa0/0 of Router 2 and another crossover cable from fa0/1 on R2 to fa0/0 of R3.
I have noticed that when I have been configuring the interface and IP for each router and fast ethernet port on it, that after I do the "no shut" command, I get a message that "Line protocol on interface FastEthernet0/0 changes state to up." that is then followed automatically by "Line protocol on interface FastEthernet0/0 changes state to down." and I have no idea why this is. I am also noticing that the ports that my crossover cables are plugged into are not lit up on any of the routers.
Here are the show run info for each of the 3 routers:
R1:
interface FastEthernet0/0
ip address 192.168.1.1 255.255.255.0
duplex auto
speed auto
random-detect
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/0/0
no ip address
shutdown
!
interface Serial0/1/0
no ip address
shutdown
!
ip forward-protocol nd
no ip http server
no ip http secure-server
____________________________________________
R2:
interface FastEthernet0/0
ip address 192.168.1.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/0/0
no ip address
shutdown
!
interface Serial0/1/0
no ip address
shutdown
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
!
!
!
!
!
!
!
!
control-plane
!
!
!
line con 0
logging synchronous
line aux 0
line vty 0 4
login
transport input all
!
scheduler allocate 20000 1000
end
________________________________________________________
R3:
interface FastEthernet0/0
ip address 192.168.2.3 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/0/0
no ip address
shutdown
!
interface Serial0/1/0
no ip address
shutdown
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
!
!
!
!
!
!
!
!
control-plane
!
!
!
line con 0
logging synchronous
line aux 0
line vty 0 4
login
transport input all
!
scheduler allocate 20000 1000
end
Solved! Go to Solution.
04-03-2019 11:24 PM
Hi there,
Can you share the output of sh int fa0/0
There is a chance the interface may be faulty, have you tried moving the config to fa0/1 and connecting to that? You will need to:
conf t ! default int fa0/0 ! exit
There is also a good chance the cross-over cable has been badly crimped. Do you have another one you could try?
cheers,
Seb.
04-03-2019 11:24 PM
Hi there,
Can you share the output of sh int fa0/0
There is a chance the interface may be faulty, have you tried moving the config to fa0/1 and connecting to that? You will need to:
conf t ! default int fa0/0 ! exit
There is also a good chance the cross-over cable has been badly crimped. Do you have another one you could try?
cheers,
Seb.
04-08-2019 03:16 PM
Thank you guys for your help so far. The ports are definitely good as they light up when my laptop with the straight cable is plugged into any of them. I'm sure the crossover cables are fine as well.This is what it shows for sh interface for each of my routers:
R1:
Router#sh int fa0/0
FastEthernet0/0 is administratively down, line protocol is down
Hardware is Gt96k FE, address is 40f4.ec7c.f9d2 (bia 40f4.ec7c.f9d2)
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Auto-duplex, Auto Speed, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
_________________________________________________________________
R2 Router#sh int fa0/0
FastEthernet0/0 is administratively down, line protocol is down
Hardware is Gt96k FE, address is e804.62de.bfea (bia e804.62de.bfea)
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Auto-duplex, Auto Speed, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
______________________________________________________________________
R3
Router>sh int fa0/0
FastEthernet0/0 is administratively down, line protocol is down
Hardware is Gt96k FE, address is 68bd.ab7b.ffba (bia 68bd.ab7b.ffba)
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Auto-duplex, Auto Speed, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
04-08-2019 11:24 PM
Hi there,
Looking at your sh int output, all of the interfaces in an admin-down state. As @Deepak Kumar pointed out earlier, for each of the interface you are using, issue the no shut command, eg:
!! R1 ! int fa0/0 no shut !
Do this on every interface along the path between R1 and R3.
cheers,
Seb.
04-14-2019 02:15 PM
Thank you, Seb. I think I finally figured out the problem. So every single time I would do the no shut command, it would ALWAYS spit out a "changed state to up" line follow immediately by a "changed state to down" line no matter what I tried. Finally, I swapped my crossover cable for a different one included in my kit and now the ports light up as they should and I can ping R2 from R1, etc. Some cables that were including in my kit were labeled "T1 crossover cables" and those were the ones I was originally using. Other cables, upon closer examination were labeled "Cat 5E crossover patch cable". After using the latter, things seem to be working now. I guess the T1 crossover cables are only to be used in the T1 DSU/CSU ports in my routers and that's why it didn't work? Still kind of confusing to me, but I appear to be able to move along now. I really appreciate your help.
04-15-2019 12:57 AM
Hi there,
T1 and Ethernet crossover cables are wildly different and as such use different pairs to operate. Check the pin outs of both cables side by side, better still google the wiring diagrams of both types.
cheers,
Seb.
04-04-2019 12:25 AM
Hello,
on a side note, there used to be the interface command 'loopback' which was sort of an internal self test. If you configure that on the interface, the interface should go to up/up if it is not faulty...
You could also just connect a straight cable to the ports with a PC attached in order to at least verify that the ports work.
04-04-2019 01:34 AM
Hi,
Make some changes as below:
R1:
ip route 192.168.2.0 255.255.255.0 192.168.1.2
R2:
interface FastEthernet0/1
ip add 192.168.2.2 255.255.255.0
no shutdown
R3:
ip route 192.168.1.0 255.255.255.0 192.168.2.2
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