Tracert and Default Route

[jtrogdon]

I have three Cisco routers and a Netopia Cable modem router. The Commerce network is setup as 192.168.4.0 on Serial0 and 192.168.5.0 on Ethernet0.

The Plant49 router is setup on network 192.168.4.1 on Serial0 and 192.168.2.1 on Serial1 and 192.168.3.0 on Ethernet0.

The third Cisco router is at a plant I call Central but it doesn't fall into what I'm trying do here.

My Netopia cable modem router is on address 192.168.3.10 located at Plant49. I can ping and telnet to the Netopia from the Commerce plant. I can ping from Plant49 (192.168.3.0) to addresses on the 192.168.5.0 network.

Here's my routing table from my Commerce router:

Gateway of last resort is not set

192.168.4.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.4.0/24 is directly connected, Serial0

C 192.168.4.1/32 is directly connected, Serial0

C 192.168.5.0/24 is directly connected, Ethernet0

R 192.168.1.0/24 [120/2] via 192.168.4.1, 00:00:25, Serial0

192.168.2.0/24 is variably subnetted, 2 subnets, 2 masks

R 192.168.2.2/32 [120/1] via 192.168.4.1, 00:00:25, Serial0

R 192.168.2.0/24 [120/1] via 192.168.4.1, 00:00:25, Serial0

R 192.168.3.0/24 [120/1] via 192.168.4.1, 00:00:25, Serial0

I have my static address at Commerce set at 192.168.5.10 set on the workstation. My gateway is setup as 192.168.3.10 (The Netopia cable modem at Plant 49). My DNS on the workstation is setup as 192.168.3.10 because the Netopia is forwarding the DNS queries.

I can ping all my local addresses (192.168.x.x) but if I try to tracert an Internet address this is what I get:

C:\>tracert 205.152.0.8

Tracing route to 205.152.0.8 over a maximum of 30 hops

1 2 ms 2 ms 2 ms 192.168.5.1

2 192.168.5.1 reports: Destination host unreachable.

Trace complete.

My guess is that I need a default route on the Commerce router. So do I set it like this:

ip route 0.0.0.0 0.0.0.0 serial0

or

ip route 0.0.0.0 0.0.0.0 192.168.3.10

I was also wondering how this would affect any network performance by setting this default route. I just need the Commerce workstation to get to the Internet through the Netopia cable modem router at Plant49.

Any suggestions? Thanks for your help.

[dbellazetin]

For this to work you would need two default routes. One for the Commerce router and another on the Plant49 router.a

It looks like you are running RIP and learning about networks from your Plant49 router via your serial0 interface.

You could do 2 things.

Option 1 - Static default routes on both routers

On your Commerce router

ip route 0.0.0.0 0.0.0.0 192.168.4.1

On your Plant49 router

ip route 0.0.0.0 0.0.0.0 192.168.3.10

Once both routes are configured you should be able to trace to an internet address and access the internet.

Option 2 - Default route on Plant49 redistributed into RIP.

On Plant49 router

ip route 0.0.0.0 0.0.0.0 192.168.3.10

router rip

redistribute static

Once this has been done you should be seeing a default route learned on your Commerce router pointing to the Plant49 router.

*One more thing I wanted to add is the workstation on the Commerce router ethernet segement should have its default gateway set to the Commerce router 192.168.5.x.

Daniel

[jtrogdon]

Thanks for the response. I'll try that as soon as possible.

By setting up these default routes will this in any way interfere with regular IP traffic on my 192.168.x.x network? In other words, all my 192.168.x.x devices can see each other without any static routes. Will adding these default routes cause any additional or unwanted traffic?

Thanks for the help.

[dbellazetin]

Default routes are last resort routes so it shouldn't effect the current communications between your networks. It will still use the more specific routes for reachability. The only change is that your default route will now route packets of unknown destiation's to where ever you point them.

As far as default routes are concerned they will not impact anything unless there are other default routes in other routers already configured which we must add into the picture.

Daniel

[jtrogdon]

Ok, I ran into a problem when I added the static address at the Plant49. My email server is located at the Central plant. It looked like it picked up the static route via RIP was redirecting incoming traffic to my 192.168.2.0 network. I removed the static route from Plant49 and my incoming email started working again. How do I prevent this? Do I need to added a static default route to the 192.168.2.0 network redirecting it to 192.168.1.1 which is the address of my email server?

[dbellazetin]

I need to see the picture from all your routers. Can you post the configs, and show ip route from all your routers.

We may need to enforce policy routing to achieve the desired results.

Daniel

[jtrogdon]

I have attached my router configs for you.

[jtrogdon]

I have attached my "show ip route" results for each plant. Thanks very much for your help.

[dbellazetin]

Ok. I was expecting to see another default route already in the picture but there was not.

What you can do is add a default route to your plant49 router and do not do the redistribute static command under RIP.

If you'd like to discuss these details more clearly and answer all the questions we each have you can e mail me your contact information and I will contact you directly.

Daniel

dbellazetin@dynix.com

[jtrogdon]

I think I finally got it figured out. Since I needed to NOT have the static route distributed over RIP I did this:

router rip

distribute-list 3 out

access-list 3 deny 0.0.0.0

Access-list 3 permit 0.0.0.0 255.255.255.255

That denies routes that are to "0.0.0.0" from being redistributed over rip but permits all others (the second access list line).

This allowed the Commerce to use the static route to Plant49 and then on to the Internet.

Thanks for your help and suggestions.