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Routing public packets to private pc

By johnnyextreme ·
(IP addresses are bogus) I have private network PC 10.0.1.15 with gateway router Cisco 1600 10.0.1.1 connected over 56k WAN link to Cisco 1600 10.0.0.150 which is on network connected to internet via Cisco 2600 T1 router 10.0.0.1 / 216.251.125.129.Cisco 2600 216.251.125.129 is configured to forward all packets addressed to 216.254.125.160 to 10.0.1.15. Ping of 216.254.125.160 gives reply from 10.0.0.150 'TTL expired in Transit'. 10.0.1.15 is pingable from either subnet on private network. How do I troubleshoot this?

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Routing public packets to private pc

by Kevin Anderson In reply to Routing public packets to ...

Start by using traceroute. (try www.visualware.com to download visual route (30 day demo) if you're not too experienced with traceroute already).

Try pinging the cisco 2600. If that works, then try pinging the 1600 (10.0.0.150) If that works,then try pinging the other 1600 10.0.1.1. I suspect that this router will fail to reply. Which indicates to me that your Ping requests aren't making it across the 56K wan.

make sure that there is a route on 10.0.0.150 listing 10.0.1.1 as the gateway.

I suspect that pinging 10.0.1.15 will fail even from the 10.0.0.??? network. Both networks can see 10.0.0.150, but 10.0.0.150 will not route from 10.0.0.x to 10.0.1.x.

Put in a route for 10.0.1.0 (mask 255.255.255.0) through the 10.0.1.1 gateway, and you should be fine.

Kev.

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Routing public packets to private pc

by johnnyextreme In reply to Routing public packets to ...

pc 10.0.1.15, 2600 router 10.0.0.1 and 216.251.125.129, 1600 router 10.0.0.150 and 1600 router 10.0.1.1 are all pingable from 10.0.0.x addresses. Tracert from 10.0.0.52 to 216.254.125.160 bounces back and forth between 216.251.125.129 and 10.0.0.150 (loop). but I see that there is a FQDN for 216.254.125.160 so it is registered in our ISPs DNS, does that matter?

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Routing public packets to private pc

by -Q-240248 In reply to Routing public packets to ...

Routers route between subnets, not amongst one. You'll need different subnets with different subnet masks. It also depends on your routing protocols. (RIP, OSPF, EIGRP...etc) Showing your router configurations ('sh ru' command on the Cisco) would behelpful...Just keep in mind that you'll need a couple of different internal networks. Simply subnet the 10.0 network you were using.

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Routing public packets to private pc

by johnnyextreme In reply to Routing public packets to ...

Don't I have different subnets? The 1600 routers 10.0.0.150 and 10.0.1.1 route between the 10.0.0.x and 10.0.1.x subnets over the 56K WAN link. The 2600 router routes between these internal networks and the internet. An outside packet destined for 216.254.125.160 should arrive through 216.251.125.129 then hop to 10.0.0.150 then hop to 10.0.1.1 then hop to 10.0.1.15. It looks to me like 10.0.0.150 believes the packets should go to 216.251.125.129, so they loop until TTL expires.

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Routing public packets to private pc

by wcraigmiles In reply to Routing public packets to ...

First the other people are correct. You have not given us enough information to help you.

Second, are using routing or static routes?
Looks like you need to remove the routing protocols and use static routes.

Third, I think there are a couple of other problems happening on your network but can't tell from what you've given.

Is IP the only protocol on the network? Are you combining EIGRP and RIP? Are you propagating incorrect route summary? Do you have any access lists applied? Particularly do you have any extended access lists applied? What are the subnet masks applied? Are you using variable lenght subnet masks, are you using a classful routing protocol or one that supports VLSM?

If you walk through those questions, the answer should fall out.

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Routing public packets to private pc

by johnnyextreme In reply to Routing public packets to ...

I apologize for not giving enough info. As for the questions you asked, the only one I know the answer to is the first - Yes IP is the only protocol. I know very little about routers. I got the solution from my ISP tech support. My internal routers(1600's) had no route for external IP addresses. They had me Telnet into 10.0.0.150 and enter config mode, type "IP ROUTE 216.254.125.160 10.0.1.1", save that, then telnet into 10.0.1.1 and enter "IP ROUTE 216.254.125.160 10.0.1.15", save that, alsomake sure the 10.0.1.15 machine has 216.254.125.160 as a second IP address (TCP/IP Advanced properties) with 255.255.255.192 as a subnet mask. It was a very simple solution, but I was ignorant of the ways of routers.

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Routing public packets to private pc

by johnnyextreme In reply to Routing public packets to ...

This question was closed by the author

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Routing public packets to private pc

by johnnyextreme In reply to Routing public packets to ...

The Cisco 2600 was configured correctly, but the two 1600 routers had no route for 216.254.125.160, so the first 1600 (10.0.0.150) would send the packets right back to the 2600, causing a loop. Entering a route into 10.0.0.150 for 216.254.125.160 to 10.0.1.1, then into 10.0.1.1 for 216.254.125.160 to 10.0.1.15, then giving 10.0.1.15 a second IP address of 216.254.125.160 under TCP/IP Advanced Properties solved the problem.

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