1721 Router Setup

[thoppenrath]

I trying a new post because I've simplified my setup. I'm just learning and I can't seem to get a simple example to work. Following is my setup, I want to be able to Ping the laptop on Network 2. I can telnet to the router and ping it but I can't ping it from network 1.

Below is the router config.

------------------------------------------------------------------------------------

show config

Using 677 out of 29688 bytes

!

! Last configuration change at 03:40:45 UTC Mon Mar 31 2008

! NVRAM config last updated at 03:40:53 UTC Mon Mar 31 2008

!

version 12.2

service timestamps debug datetime msec

service timestamps log datetime msec

no service password-encryption

!

hostname TestRouter

!

logging queue-limit 100

enable secret xxxx

enable password xxxx

!

ip subnet-zero

!

!

!

!

!

!

!

interface Ethernet0

ip address 10.20.20.77 255.255.255.0

half-duplex

!

interface FastEthernet0

ip address 10.10.7.1 255.255.0.0

speed auto

!

ip classless

no ip http server

!

!

!

line con 0

exec-timeout 0 0

password xxxx

login

line aux 0

line vty 0 4

password xxxx

login

!

end

Thanks!

[Brian Meade]

From what I read, it sounded as if he could only ping the laptop from the router, but I could be wrong.

[paolo bevilacqua]

Hi, with all the respect due for opinions collected at the office (we have great football talks often), no routing protocol is needed to route between connected networks, ever.

[wardp1000]

Would I be correct in thinking:

Network 1 (desktop):

--------------------

IP address: 10.10.3.10/16

Gateway : 10.10.7.1

1721

----

fe0: 10.10.7.1

e0 : 10.20.20.77

Network 2 (laptop)

------------------

IP address: 10.20.20.50/24

Gateway : 10.20.20.77

1. Ping 10.20.20.50 from the desktop fails

2. Ping 10.10.7.1 from the laptop success?

If this is the case then I suspect you have a firewall issue. What Rick said about being able to ping the router “If the router can ping to the desktop then it shows that the issue is not a firewall running on the desktop” isn't strictly true with many firewalls. The firewall on XP for example will allow an echo response to a device on the same network, ie 10.10.x.x/16 but will block echo response to devices on other networks, ie. 10.20.20.x/24. Turn off the firewall on the desktop and try a ping from the laptop to the desktop again.

Thank you

Peter

[Richard Burts]

Paolo

Thanks for confirming my assertion that no routing protocol is needed for routing between connected subnets.

Peter

Thanks for the information. I was not aware of that aspect of the firewall for XP. It would explain the behavior of the problem very nicely. So my suggestion of using extended ping to source the ping from the other subnet would help to show that the behavior changes based on what is the source address of the ping.

HTH

Rick

[thoppenrath]

Thanks everyone for the help. I got the laptop pinging the PC by changing it's GW to 10.20.20.77. BTW, I didn't have to add any routing statements to the config.