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New Member

Can't ping internal network

Hi, I have one Cisco 1751 that connects to a Cisco 2620 thru dialup Async ports using 2 analog lines. The Cisco 1751 connects to the other

router with no problem. I have static routes to the remote segment. I

am able to ping the Async port and the Ethernet port of the remote Cisco 2620, I can also ping a PC at the remote segment, however I can't ping any other device on the remote segment. Is there any reason why I can ping that PC but I can't ping any other device ?? That PC has been used to telnet to the router on the remote site. Does this problem has anything to do with not been able to do ARP over the Async line ?? Any suggestions will be highly appreciated.

Suikam Kwok

Benchmark Computer Systems, Inc.



New Member

Re: Can't ping internal network

check for:

-static routes in both sites: routes must be for all hosts (check mask)

-gateway in other PC you could not ping

-route table in PC you could not ping (route print)

u can use tracert from the dos to check where the ping stops.

New Member

Re: Can't ping internal network

Thanks for the suggestions but all this has been checked.

New Member

Re: Can't ping internal network


During you can ping one of your PC's on the 2600 segment, your routing appears OK. This is how I would proceed.

- Take down the async line. Put the IP address of the ethernet interface of the 1700

on a loopback interface on the 2600.

- Move the ip address on the 2600's async interface to another loopback


- Once you have done the above, do an extended ping to different devices on

the 2600's LAN using the loopback interfaces as the source addresses. If

the pings work, their is a problem over the async. If they do not, the problem is

on your local LAN.

- If the problem appears to be over the async connection, do some IP packet

debugs to see what it is saying.


New Member

Re: Can't ping internal network

Thanks for your advise. I tried what you said and I can ping the devices. If I do a debug ip packet I see the 2620 sending and receiving multicasts from different stations including the remote 1751 router. What does this means ????

New Member

Re: Can't ping internal network

From the 2620 can you ping the other devices that are unreacheable for the 1751?


New Member

Re: Can't ping internal network

Yes, I can ping everything in the 2620 local network from the 2620. And I also can ping everything in the 1751 network from the 1751 router. I can ping from one router to the other all of its interfaces. I just can't reach any device in each other's network. I have even tested with RIP, IGRP, static routes and the routers are learnig each others route to the internal network.

New Member

Re: Can't ping internal network

I can imagine this situation that case if on the remote PCs not configured properly the default gateway.

Or if your remote site has more router and the default router not this 2620, and the default route don't know the 1750's site..