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Help with a simple Cisco routing question

Hello Experts,

I’ve picked up some Cisco equipment to play around with.  Here is my setup:

2 routers connected via a serial link.  

The serial interface on Router1 is configured as follows:
interface Serial0/1/0
ip address 10.0.0.1 255.255.255.252
clock rate 4000000

The serial interface on Router2 is configured as follows:
interface Serial0/1/0
ip address 10.0.0.2 255.255.255.252

FastEthernet0/0 on Router1 is the default gateway for a laptop I have connected to Router1.  The configuration of FastEthernet0/0 is as follows:
interface FastEthernet0/0
ip address 192.168.10.254 255.255.255.0
duplex auto
speed auto

The routing table on Router1 is as follows:
Gateway of last resort is not set

     10.0.0.0/30 is subnetted, 1 subnets
C    10.0.0.0 is directly connected, Serial0/1/0
C    192.168.10.0/24 is directly connected, FastEthernet0/0

The IP configuration on the laptop connected to Router1 is as follows:
IP address = 192.168.10.10
Subnet Mask = 255.255.255.0
Default gateway = 192.168.10.254

From Router1 (10.0.0.1), I can successfully ping Router2 (10.0.0.2).
From the laptop, I can successfully ping the default gateway (192.168.10.254).
From the laptop, I can successfully ping the serial interface on Router1 (10.0.0.1).  However, I cannot ping the far side of the point-to-point connection on Router2 (10.0.0.2), and I don’t know why.  Router1 obviously knows about the 10.0.0.0 network as it is shown as connected in the routing table.  Why can’t I ping 10.0.0.2 from the laptop?  Any explanation would be greatly appreciated.

Regards,
Nick
0
ndalmolin_13
Asked:
ndalmolin_13
2 Solutions
 
Syed_M_UsmanSystem AdministratorCommented:
Dear,
Thank you for posting your question on EE.

try below command on both routers;
ip route 0.0.0.0 0.0.0.0 Serial0/1/0
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PredragNetwork EngineerCommented:
Router R1 knows how to ping 10.0.0.2, that is not issue here.
Issue is that router R2 does not have any information about 192.168.10.0/24.

try on router R2 command
R2#debug ip icmp
and then ping 10.0.0.2 from desktop
You will see that pings are coming to router R2, but router R2 does not now way  back to network 192.168.10.0
You have two solutions:
set static route on router R2 to network 192.168.10.0
turn on some routing protocol (rip, eigrp, ospf) on both routers
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ndalmolin_13Author Commented:
Thank you.  Both recommendations worked.  The debug command gave good information
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