Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
New Member

routing problem

Hi

I have two routers connected via frame-relay(point-to-point).

router 1

s0/0.1 - 1.1.1.1

s0/0.2 - 2.2.2.2

f0/0 - 3.3.3.3

router 2

s0/0.1 - 1.1.1.2

s0/0.2 - 20.20.20.20

f0/0 - 30.30.30.30

from router1 I can ping all the interfaces of the router2.

There are two networks behind router2 5.5.5.5 and 6.6.6.6, from router2 I can ping both the networks but when I try to traceroute from router1 on any of the networks it only reaches till 1.1.1.2 (router2 serial interface) and cannot find both the network. I can't ping them as well.

I checked the routing and everything is ok. I am using OSPF as routing protocol and in router1 I can see that it has discovered the correct path for the network.

Can anyone please help me that why I can't ping the network behind the router. I can ping all both the networks from router2 but not from router1.

thanks

2 ACCEPTED SOLUTIONS

Accepted Solutions
New Member

Re: routing problem

Do 5.5.5.5 and 6.6.6.6 know how to get back to router 1 (1.1.1.1)? It could very well be that your pings are making it to the destination networks but get lost coming back.

Kevin

Gold

Re: routing problem

On router1, do an extended ping, sourcing the ping from one of the serial interfaces, instead of the default source:

2651A#ping

Protocol [ip]:

Target IP address: 5.5.5.5

Repeat count [5]:

Datagram size [100]:

Timeout in seconds [2]:

Extended commands [n]: y

Source address or interface: serial0/0

Type of service [0]:

Set DF bit in IP header? [no]:

Validate reply data? [no]:

Data pattern [0xABCD]:

Loose, Strict, Record, Timestamp, Verbose[none]:

Sweep range of sizes [n]:

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 5.5.5.5, timeout is 2 seconds:

If this fails, then 5.5.5.5 doesn't know how to get off segments, which implies its default gateway is wrong, or, if it's a router, that it isn't hearing about the routes attached to router 1. If it's a router, are you running ospf with that router as well? Can you do a show ip ospf nei, and see if the adjacency is up?

If not, then we need to troubleshoot that. Generally, a debug ip ospf neighbor will tell us what's wrong there.

Russ.W

6 REPLIES
New Member

Re: routing problem

Do 5.5.5.5 and 6.6.6.6 know how to get back to router 1 (1.1.1.1)? It could very well be that your pings are making it to the destination networks but get lost coming back.

Kevin

New Member

Re: routing problem

Hi Kevin

I have checked and the routes are there because I can ping 3.3.3.3 from both the networks.

thanks

Gold

Re: routing problem

On router1, do an extended ping, sourcing the ping from one of the serial interfaces, instead of the default source:

2651A#ping

Protocol [ip]:

Target IP address: 5.5.5.5

Repeat count [5]:

Datagram size [100]:

Timeout in seconds [2]:

Extended commands [n]: y

Source address or interface: serial0/0

Type of service [0]:

Set DF bit in IP header? [no]:

Validate reply data? [no]:

Data pattern [0xABCD]:

Loose, Strict, Record, Timestamp, Verbose[none]:

Sweep range of sizes [n]:

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 5.5.5.5, timeout is 2 seconds:

If this fails, then 5.5.5.5 doesn't know how to get off segments, which implies its default gateway is wrong, or, if it's a router, that it isn't hearing about the routes attached to router 1. If it's a router, are you running ospf with that router as well? Can you do a show ip ospf nei, and see if the adjacency is up?

If not, then we need to troubleshoot that. Generally, a debug ip ospf neighbor will tell us what's wrong there.

Russ.W

New Member

Re: routing problem

Hi Russ,

I have checked the routes and its ok because I can ping 3.3.3.3 from 5.5.5.5 and 6.6.6.6 without any problem but I can't ping both the networks from 3.3.3.3

I can ping both the networks from router2 but not from router1.

And when I traceroute from router1 I can see the next hop i.e. router2 and thats it.

And currently I am not using any access-list to block any traffic.

Is there any debugging or anything else I can do?

I have added the static routes

thanks

New Member

Re: routing problem

Hi Russ,

I tried the extended ping from interface 3.3.3.3 and it works but if I try normal ping its not working.

Thanks

Nitin

New Member

Re: routing problem

Hi Guys,

Thanks for the help, I fold out it was routing problem. As I only added the routes for 3.3.3.3 and not for 1.1.1.1, So when I was doing normal ping it was going out via 1.1.1.1 and in 5.5.5.5 it doesn't know how to reach 1.1.1.1 but when I was doing extended ping and use 3.3.3.3 it always worked because there were routes for this interface.

thanks for the help

154
Views
0
Helpful
6
Replies
CreatePlease to create content