Route Question/Problem

Router1 - e0 has the ip 192.168.1.240/24 and s0 has the ip 172.16.120.105/24.

Router#show ip route
Gateway of last resort is 0.0.0.0 to network 0.0.0.0

172.16.0.0/24 is subnetted, 1 subnets
C 172.16.120.0 is directly connected, Serial0
C 192.168.1.0/24 is directly connected, Ethernet0
S* 0.0.0.0/0 is directly connected, Ethernet0

I can ping anything on the 192.168.1.0/24 I can also ping the far end of the FR connection 172.16.120.120.

Router2 - s0 has the ip 172.16.120.120/24.

Router#show ip route
Gateway of last resort is 0.0.0.0 to network 0.0.0.0

172.16.0.0/24 is subnetted, 1 subnets
C 172.16.120.0 is directly connected, Serial0
S* 0.0.0.0/0 is directly connected, Serial0

I can ping the far end of the FR connection (172.16.120.105).

The problem is I can't ping anything on the 192.168.1.0 network. Is this because they are both RFC1918 private networks? Is there something I'm missing? Is there additional info that is needed to figure this out? For the most part I haven't done anything else to these.

Thanks in advance!

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Comments

jbrad95706

Just want to add that I tossed rip on both routers, and still no luck...

R1
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.120.0 is directly connected, Serial0
C 192.168.1.0/24 is directly connected, Ethernet0
S* 0.0.0.0/0 is directly connected, Ethernet0

R2
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.120.0 is directly connected, Serial0
R 192.168.1.0/24 [120/1] via 172.16.120.105, 00:00:02, Serial0
S* 0.0.0.0/0 is directly connected, Serial0

bighornsheep

Private addressing wouldn't affect pinging in your setup unless you have some kind of NAT configuration involved.

Is this setup configured on real equipment or some kind of IOS simulator?

If the IOS supports it, try to do a source ping from R1 like this:

ping 172.16.120.120 source e0

and see what happens. If it doesn't work, do a write erase on the routers and start again. I noticed you have default gateway configured on the routers, take that on R1, and have only a default route on R2 and see if it works.

You're doing the right things; I suspect it's problems with old config, or a bug on your simulator (if you're using one).

Good luck.

Forsaken_GA

you should be able to ping the 192.168.1.240 address from Router 2, especially with RIP active. Is that not the case?

If your trying to ping IP's other than the .240 address on the 192.168.1.0/24 subnet, it may sound stupid, but make sure the hosts you're trying to ping have a route back to Router2 (ie, make sure they have a default gateway defined)

It's hard to say what might be at issue without seeing your topology or your configs

tech-airman

jbrad95706,

jbrad95706 wrote: »

Router1 - e0 has the ip 192.168.1.240/24 and s0 has the ip 172.16.120.105/24.

Do you have a cable plugged into the e0 interface of Router1?

jbrad95706 wrote: »

Router#show ip route
Gateway of last resort is 0.0.0.0 to network 0.0.0.0

172.16.0.0/24 is subnetted, 1 subnets
C 172.16.120.0 is directly connected, Serial0
C 192.168.1.0/24 is directly connected, Ethernet0
S* 0.0.0.0/0 is directly connected, Ethernet0

I can ping anything on the 192.168.1.0/24 I can also ping the far end of the FR connection 172.16.120.120.

Router2 - s0 has the ip 172.16.120.120/24.

Router#show ip route
Gateway of last resort is 0.0.0.0 to network 0.0.0.0

172.16.0.0/24 is subnetted, 1 subnets
C 172.16.120.0 is directly connected, Serial0
S* 0.0.0.0/0 is directly connected, Serial0

I can ping the far end of the FR connection (172.16.120.105).

The problem is I can't ping anything on the 192.168.1.0 network. Is this because they are both RFC1918 private networks? Is there something I'm missing? Is there additional info that is needed to figure this out? For the most part I haven't done anything else to these.

Thanks in advance!

jbrad95706

bighornsheep wrote: »
Private addressing wouldn't affect pinging in your setup unless you have some kind of NAT configuration involved.

Is this setup configured on real equipment or some kind of IOS simulator?

If the IOS supports it, try to do a source ping from R1 like this:
ping 172.16.120.120 source e0
and see what happens. If it doesn't work, do a write erase on the routers and start again. I noticed you have default gateway configured on the routers, take that on R1, and have only a default route on R2 and see if it works.

You're doing the right things; I suspect it's problems with old config, or a bug on your simulator (if you're using one).

Good luck.

No NAT, and It is real hardware - I have two 2520's setup with a "Back-to-Back Frame Relay Hybrid" setup. From there e0 connects to my home router (Belkin), and it has my PC off one of the ports.

(R2)s0---s0(R1)e0---Someport(Belkin)Someport---Nic(PC)

The source ping to .120 worked.

Then I removed the default gateway and tried again, but still no joy.

jbrad95706

Forsaken_GA wrote: »

you should be able to ping the 192.168.1.240 address from Router 2, especially with RIP active. Is that not the case?

If your trying to ping IP's other than the .240 address on the 192.168.1.0/24 subnet, it may sound stupid, but make sure the hosts you're trying to ping have a route back to Router2 (ie, make sure they have a default gateway defined)

It's hard to say what might be at issue without seeing your topology or your configs

Hmm, the ping to .240 worked.

Silly of me not to try and ping it, I tried the default gateway (192.168.1.1) and the PC (.3) and when they failed I assumed the worse. So, I can hit e0 on R2 - just nothing past R2.

jbrad95706

tech-airman wrote: »

jbrad95706,

Do you have a cable plugged into the e0 interface of Router1?

It's in e0 on R2 - from R2 I can hit the Belkin and the PC, just not from R1.

(R2)s0---s0(R1)e0---Someport(Belkin)Someport---Nic(PC)

jbrad95706

Also, I can hit (R2 e0) .240 from the PC.

Edit:

I also pulled out the Belkin for a moment to see if for so reason that was the issue, but it still didn't work.

jbrad95706

Found the issue!

So, I fired up wireshark on the PC - the ping is hitting the PC; however, Vista is not responding to the 172.16.x.x address. I assume it's some MS security saving me from myself!

Also, I'm guessing the Belkin will forward, but not reply to internal non-192.x.x.x addresses.

Thanks everyone!

Edit: Just to add a little more info...

Turning off the Windows Firewall allows Vista to reply; however, (I assume) the Belkin doesn't know what to do with the traffic. Just to make it even better - if I remove the Belkin and connect the 2520 right to the PC Vista stops replying to the 172x.x.x address again...

Either way the Cisco gear is setup right, and they are hitting the PC and I assume the Belkin.