CCNA NetAcad Hands-on Lab 1.5.2: Help needed to understand

workfrom925

I'm doing CCNA Basic Router Configuration Hands-on Lab 1.5.2. At the end of the lab, I can't ping 192.168.3.1 on FastEthernet0 on R2 from PC1, which is fine. However, while the procedure Step 7 (listed below) says I shouldn't be able to ping R2 from PC1, I can actually ping router R2's serial port (192.168.2.2). Why?

From Router R2, I was able to ping 192.168.1.1 on R1's fastEthernet0 and 192.168.1.9 on the switch's VLAN1, but I can't ping PC1, which has 192.168.1.2. I assume, under normal circumstances, if I can reach one IP in a subnet, I should be able to reach all other IP in the subnet? No?

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To help, I copy R2 routes and pings here:

R2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

S 192.168.1.0/24 is directly connected, Serial0
C 192.168.2.0/24 is directly connected, Serial0
C 192.168.3.0/24 is directly connected, FastEthernet0
R2#ping 192.168.2.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.2.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/3/4 ms
R2#ping 192.168.1.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
R2#ping 192.168.1.9

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.9, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms
R2#ping 192.168.1.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R2#

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Copied from the Lab 1.5.2 PDF file:

Task 7

Reflection


Step 1

Attempt to ping from the host connected to R1 to the host connected to R2

This ping should be unsuccessful.


Step 2

Attempt to ping from the host connected to R1 to router R2

This ping should be unsuccessful.


Step 3

Attempt to ping from the host connected to R2 to router R1

This ping should be unsuccessful.


What is missing from the network that is preventing communication between these devices?

Ltat42a

Does R1 have 192.168.3.0 in its routing table? If it don't, pings won't go through.

workfrom925

Ltat42a wrote: »

Does R1 have 192.168.3.0 in its routing table? If it don't, pings won't go through.

Yes. R1 doesn't have the route for 192.168.3.0. So PC1 can't ping anything in 192.168.3.0. I understand that.

What I don't understand is, PC1 was able to ping R2's serial port (192.168.2.2). The lab material says I should not be able to do this (Quote from the lab material: Attempt to ping from the host connected to R1 to router R2. This ping should be unsuccessful.).

And from R2, I was able to ping R1's fastEthernet0 (192.168.1.1), but not PC1 (192.168.1.2) in the same subnet. My understanding is, under normal circumstance, if I can ping one IP in a subnet, I can ping other IP in the same subnet? Am I correct?

Ltat42a

Yeah, you should be able to.

Ltat42a

I created that lab in packet tracer. I added a static route on R2 to the 192.168.1.0 network. Pings from R2 to PC1 went through fine. Pings from Pc1 to R2 failed. I added a static route on R1 to the 192.168.3.0 network, pings from PC1 & R2 go back & forth just fine.