Router problem (with pic)

Hosts on the 192.168.1.0 network can ping the 2501a, but they cannot ping anyone on the 2501b. Cant even ping anything on the 2501b. Ideas? I did RIP as follows:

2501a: network 192.168.1.0
network 192.168.0.0

2501b: network 192.168.0.0
network 192.168.2.0

Should the 2501a be in a different network than the sohoware routerr?
thanks

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Comments

dissolved

pic added, thanks

viper75

Router A does not have to be in a different network from your gateway.

My setup at home goes like this:

Linksys Router(Host Connected A, B, C, D)--->2900(Host E & F)--->2500--->2500--->2500--->2500--->2900(w/ Host G,H)--->2900--->(Host I & J)

I have RIP Configured on all routers. Network address is 192.168.1.0/24

I can telnet from all host to any switch\router, browse network, and surf the web.

Can you show us your routers configuration? I'm pretty sure there's a simple mis-configuration somewhere.

dissolved

Figured it out. Router A did not have the 192.168.0.0 network added when I configured RIP.

Hey, how do I remove a rip entry that I entered wrong?
thanks man

viper75

In Global Config. mode enter:

no router rip network x.x.x.x

dissolved

thanks man

sanjana

Add below additional network statements to ur configuration:

2501a:network 192.168.2.0

2501b:network 192.168.1.0

HTH
SANJANA

dissolved

New problem. Here is the updated diagram:

1. Laptop 192.168.2.3 can ping all other routers and hosts in the network (and other hosts can ping it). But the laptop cannot ping the WAN. Why would this be?

2. I have to use the IP address when pinging from the laptop. I cannot ping with netbios names in the 192.168.2.0 network. However, I can ping with netbios names successfully in the 192.168.1.0 network. Ideas?

3. How do I remove an incorrect RIP entry from RouterB? (Viper75, I tried the command you gave me " router# no router rip network 192.168.2.1" and it did not work).

Thanks

dissolved

I'm fairly convinced the problem is DNS related. If I'm on the 192.168.2.0 network, I cannot access any computer via Netbios name. I have to use the IP.

I also cannot access the wan. DNS server cannot be reached. Do I have to add something in router 2501b, so the hosts know where dns is?

Ten9t6

try the command

config t
router rip
no network x.x.x.x

instead of stringing it all together

The segment that you can not ping any of the hosts by name....do you have anything on the segment to resolve host or netbios names? If not you will need to set up hosts or lmhost files on the pcs in that segment. An easy way for that segment to get to the internet is to setup a gateway of last resort on the routers.

Hope this gets you started..

dissolved

Ten9t6 wrote:

try the command

config t
router rip
no network x.x.x.x

instead of stringing it all together

The segment that you can not ping any of the hosts by name....do you have anything on the segment to resolve host or netbios names? If not you will need to set up hosts or lmhost files on the pcs in that segment. An easy way for that segment to get to the internet is to setup a gateway of last resort on the routers.

Hope this gets you started..

Thanks man. That worked for the RIP and the lmhost file thing. Whats weird, is that I thought windows 2000 used DNS servers to resolve NETBIOS names. Doesnt it?

When you say "set up a gateway of last resort on the routers", do you mean add a secondary gateway on both my 2500s? How would I add a gateway of last resort? I checked my book, couldnt find anything
Thanks

methoselah

Setting up a gateway of last resort (default gateway) tells the router to take crap it doesn't know how to route and pass it on to someone else to deal with.

Hosts on networks 192.168.1.0 and 192.168.0.0 and 192.168.2.0 only know to route to each other because of the route tables built by RIP on 2501a and 2501b.

Absent a static instruction of pushing all packets with destinations not in a router's route table to default out eth0/next hop, hosts on your private segments (everything to the right of 2501a) will not reach the outside world.

2501b:
- You need to make serial0 your "gateway of last resort". Do this by inserting a static route to your default gateway since you are on a stub network like so...

Cisco2501(config)#ip route 0.0.0.0 0.0.0.0 serial0

if that doesnt work, try this:

Cisco2501(config)#ip route 0.0.0.0 0.0.0.0 192.168.0.5

2501a:
- You need to make ethernet0 your "gateway of last resort". Do this by inserting a static route to your default gateway since you are on a stub network like so...

Cisco2501(config)#ip route 0.0.0.0 0.0.0.0 ethernet0

if that doesnt work, try this:

Cisco2501(config)#ip route 0.0.0.0 0.0.0.0 [gateway ip you use w/ ur Sohoware]

========

When you have done all that, show us your "show ip route" for both 2501a and 2501b

methoselah

also,

1. how are your PCs getting their IP address, SNM, gateway, and DNS addresses?

2. where is your DNS server located?

3. which book are you using?

dissolved

Thanks I will try the above.

To answer your questions

1. No DHCP is being used. I'm assigning everything manually. Which makes me think of another question. If I have the DHCP server or DNS on netowkr 192.168.1.0, will the 192.168.2.0 network be able to see it?

2. Using my ISP's DNS server

3. Sybex
Thanks again

forbesl

methoselah,

Are you getting a consulting fee for this?

dissolved

Hosts on the 192.168.2.1 network still cant access the internet, yet they can ping and access every host and device.

2501a:
I did the
ip route 0.0.0.0 0.0.0.0 192.168.0.5
sh ip route = Gateway of last resort is 192.168.0.5 to 0.0.0.0

2501b:
I did the
ip route 0.0.0.0 0.0.0.0 192.168.1.1
sh ip route = Gateway of last resort is 192.168.1.1 to 0.0.0.0

Webmaster

Configuring gateways or routes to point to a local network interface is not going to work... of course because it is meant for traffic of which the router doesn't know where to send it, setting it to send it to its own interface is not much help for the router. You can't just blast packets out of an interface and tell them to find there way somewhere out of that interface, the router needs to know the 'next hop'.

You should remove these routes, and then configure the gateway of last resort on the 2501a router to point to the cable router (which you correctly named 'gateway' in your diagram

), as that should be destination for non-local traffic.

If RIP is working between both routers, there is no need to configure a gateway on 2501b as it will receive the gateway of last resort from the 2501a router in routing updates.

Also, before you will be able to reach the internet from any network other than the 192.168.1.0 network, the cable router will need to know the route back. The default gateway of the cable router is of course pointed in the other direction, the next hop at your provider, 'the internet'. You will need to tell the cable router how it can reach the 192.168.2.0 and 192.168.0.0 networks manually by adding static routes on the cable router that point to the gateway that leads to those network. From the cable router's point of view, that would be the next hop on the local network, hence 192.168.1.40. If you can configure your cable router to join the RIP process you should do that instead.

If you can't get it to work after this, just post the entire config of both routers.

Webmaster

Just a note for readers with a similar setup, that last paragraph is not appropriate when your cable router is in 'bridging mode' and not routing. In bridging mode it has only 1 IP assigned, and works similar to using IP unnumbered interfaces on a Cisco router. If you connect a PC directly to the cable router and your PC receives a public IP address from your ISP, the cable router is bridging, not routing. In that case you would have to configure NAT on the cisco router you connect to the cable router.

If the external interface of the cable router has a public interface, and you use a private address range on the internal interface (hence, internal network, commonly 192.168.0.0 assigned by DHCP on the cable router) than the cable router is actually routing, and performs NAT.

dissolved

Thanks for everyone's help so far. Here is the sh config of 2501a:

2501a
RouterA#sh ip route

Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route

Gateway of last resort is 192.168.1.1 to network 0.0.0.0

68.0.0.0/32 is subnetted, 1 subnets
R 68.33.252.0 [120/2] via 192.168.1.1, 00:00:17, Ethernet0
192.168.0.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.0.0/24 is directly connected, Serial0
C 192.168.0.6/32 is directly connected, Serial0
C 192.168.1.0/24 is directly connected, Ethernet0
R 192.168.2.0/24 [120/1] via 192.168.0.6, 00:00:28, Serial0
S* 0.0.0.0/0 [1/0] via 192.168.1.1

2501b

RouterB#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route

Gateway of last resort is not set

R 68.0.0.0/8 [120/3] via 192.168.0.5, 00:00:12, Serial0
192.168.0.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.0.0/24 is directly connected, Serial0
C 192.168.0.5/32 is directly connected, Serial0
R 192.168.1.0/24 [120/1] via 192.168.0.5, 00:00:12, Serial0
C 192.168.2.0/24 is directly connected, Ethernet0

Here's the diagram again so you dont have to scroll:

thanks again

Webmaster

Looks like the route you added wasn't updated on the other router yet.

The show ip route output should on the second router should contain a line:
R* 0.0.0.0/0 [120/1] via 192.168.0.5, 00:00:29, Serial0

As you can see in the legend, * = candidate default

Run sh ip ro again on the 2501b and check if it is there (the gateway of last resort will also be set) if it still isn't there, try running
RouterA#clear ip ro *
and check again.

If it doesn't work, please post the entire config of both routers (sh run command).

I hope this helps!

dissolved

Thanks webmaster, here is the config of both routers.
2501a
routerA#sh config
Using 848 out of 32762 bytes
!
version 12.2
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname routerA
!
logging rate-limit console 10 except errors
enable secret 5 $1$KAWH$siTZiZob/9BtCtLubuxav/
!
ip subnet-zero
no ip finger
no ip domain-lookup
!
no ip dhcp-client network-discovery
!
!
!
!
interface Ethernet0
description Connected to LAN1 (switch)
ip address 192.168.1.40 255.255.255.0
!
interface Serial0
description connected to RouterB
ip address 192.168.0.5 255.255.255.0
encapsulation ppp
!
interface Serial1
no ip address
shutdown
!
router rip
version 2
network 192.168.0.0
network 192.168.1.0
!
ip kerberos source-interface any
no ip classless
no ip http server
!
!
!
line con 0
transport input none
line aux 0
line vty 0 4
password removed
login
!
end

2501b
RouterB#sho config
Using 854 out of 32762 bytes
!
version 12.2
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname RouterB
!
logging rate-limit console 10 except errors
enable secret 5 $1$Kw7U$zhHM0md/zOC0neIBSIz2S.
!
ip subnet-zero
no ip finger
no ip domain-lookup
!
no ip dhcp-client network-discovery
!
!
!
!
interface Ethernet0
description connected to WAP
ip address 192.168.2.1 255.255.255.0
!
interface Serial0
description connected to ROuterA
ip address 192.168.0.6 255.255.255.0
encapsulation ppp
clockrate 64000
!
interface Serial1
no ip address
shutdown
!
router rip
version 2
network 192.168.0.0
network 192.168.2.0
!
ip kerberos source-interface any
no ip classless
no ip http server
!
!
!
line con 0
transport input none
line aux 0
line vty 0 4
password removed
login
!
end

I need a beer

Webmaster

I can't find the route in your config...

Try this on router 2501a:

conf t
ip route 0.0.0.0 0.0.0.0 192.168.1.1
CTRL-z

Run show ip route (on both routers) and check if the gateway of last resort is set to 192.168.1.1

When you get to that point, where the gateway of last resort is set to 192.168.1.1 on both routers, you still need to configure that cable router as I explained a couple of posts earlier before you can get to the wan from a network behind the cisco routers.

dissolved

I did what you instructed, and I looked at my config afterwards. In router B, it looks as if it knows how to get to the WAN already. I highlighted it in red below.

RouterA

routerA#sh ip ro
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route

Gateway of last resort is 192.168.1.1 to network 0.0.0.0

68.0.0.0/32 is subnetted, 1 subnets
R 68.33.252.0 [120/2] via 192.168.1.1, 00:00:20, Ethernet0
192.168.0.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.0.0/24 is directly connected, Serial0
C 192.168.0.6/32 is directly connected, Serial0
C 192.168.1.0/24 is directly connected, Ethernet0
R 192.168.2.0/24 [120/1] via 192.168.0.6, 00:00:12, Serial0
S* 0.0.0.0/0 [1/0] via 192.168.1.1

2501b
RouterB#sho ip ro
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route

Gateway of last resort is not set

R 68.0.0.0/8 [120/3] via 192.168.0.5, 00:00:25, Serial0
192.168.0.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.0.0/24 is directly connected, Serial0
C 192.168.0.5/32 is directly connected, Serial0
R 192.168.1.0/24 [120/1] via 192.168.0.5, 00:00:25, Serial0
C 192.168.2.0/24 is directly connected, Ethernet0
RouterB#

I guess its time to add a static route in the cable router, telling it how to get to 192.168.2.0 network.

I telnetted to my cable router, and selected add static route.
It asks for:

dest
subnet mask
gateway
metric

Should I set it like this:
dest 192.168.2.0
subnet mask 255.255.255.0
gateway 192.168.0.6
metric 3 ( i used traceroute)

dissolved

by the way, RIP is enabled on the cable router. It should automatically know the way back then right?

Webmaster

Ah yes, I looked only for the default gateway when looking at your route ouput... indeed it shows that the routers learned the WAN side of the cable router by RIP. Which means, like I said in a couple of posts earlier, your router is participates in the RIP process, which also means that you don't have to configure static routes on the cable router as it should have learned the internal networks by RIP. You can probably check that on the cable router. If for some reason it did send RIP updates to the cisco routers but did not receive updates from the cisco routers, then try adding that static route. 'gateway' in that static route should be 192.168.1.40. (A gateway is the next hop on the route, NOT the last router in the path to the destination.)

Let me know if you can check the routing table on the cable router, and post the output here.

Nevertheless, that 2501b router still needs to know about that gateway of last resort, because 68.0.0.0 is not the only IP network on the Internet

The problem in your setup is that the 2501b for some reason doesn't get that static route you added (gateway of last resort). I just double-checked it with my own two 2501s and it works for me.

dissolved

Webmaster wrote:

The problem in your setup is that the 2501b for some reason doesn't get that static route you added (gateway of last resort). I just double-checked it with my own two 2501s and it works for me.

So the 2501b should be picking up the "last resort gateway" from the 2501a? I never set a last resort on the 2501b. I assumed it would automatically get it from the 2501a. Maybe my 2501b is defective?

I cannot find a way to print static routes out on my cable router.
I am going to try to add a static route in my cable router. The only thing I'm confused about is the metric . Should it be 1?
Thanks again man. Fun stuff!

Webmaster

So the 2501b should be picking up the "last resort gateway" from the 2501a? I never set a last resort on the 2501b. I assumed it would automatically get it from the 2501a. Maybe my 2501b is defective?

Yes, when you set the route to 0.0.0.0 0.0.0.0 on 2501a, 2501b should automatically (thru the RIP updates) get the following route in its table:

R* 0.0.0.0/0 [120/1] via 192.168.0.5, 00:00:29, Serial0

And the gateway of last resort on 2501b should become 192.168.0.5, automatically...

I doubt there is anything wrong with your routers as the other routes are exhanged appropriately.

I cannot find a way to print static routes out on my cable router.
I am going to try to add a static route in my cable router. The only thing I'm confused about is the metric . Should it be 1

I don't think you need to because it is probably receiving the RIP updates (as it is sending them correctly). But, yes 1 would work. It is an administrative value used for selecting the lowest cost/hop count/delay/etc route when multiple routes to the same network exist, which won't be the case if you add the static routes.

Just curious, did you configure RIP on the cable router manually or was it enabled by default?

Fun stuff!

Indeed

dissolved

Webmaster wrote:

So the 2501b should be picking up the "last resort gateway" from the 2501a? I never set a last resort on the 2501b. I assumed it would automatically get it from the 2501a. Maybe my 2501b is defective?

Yes, when you set the route to 0.0.0.0 0.0.0.0 on 2501a, 2501b should automatically (thru the RIP updates) get the following route in its table:

R* 0.0.0.0/0 [120/1] via 192.168.0.5, 00:00:29, Serial0

And the gateway of last resort on 2501b should become 192.168.0.5, automatically...

I doubt there is anything wrong with your routers as the other routes are exhanged appropriately.

I cannot find a way to print static routes out on my cable router.
I am going to try to add a static route in my cable router. The only thing I'm confused about is the metric . Should it be 1

I don't think you need to because it is probably receiving the RIP updates (as it is sending them correctly). But, yes 1 would work. It is an administrative value used for selecting the lowest cost/hop count/delay/etc route when multiple routes to the same network exist, which won't be the case if you add the static routes.

Just curious, did you configure RIP on the cable router manually or was it enabled by default?

Fun stuff!

Indeed

Ok thanks. RIP was enabled by default on my cable router. I remember seeing it in sniffer logs in the past as well.
I have no clue what to do from here lol

Webmaster

Well, you could add it manually to 2501b:

conf t
ip route 0.0.0.0 0.0.0.0 192.168.0.5

and if 'Murphy' is right, 2501a will learn it from 2501b

dissolved

I added it manually and the laptop (192.168.2.3) STILL cannot ping the wan. I used my laptop to try and ping my DNS server (I'm using my ISPs dns server). This is what happened

c: ping 68.34.76.5

Reply from 192.168.0.5 Destination unreachable

The 192.168.1.0 network can ping my dns server fine.
Hmm. This sucks.

Webmaster

ok, please post your running config (sh run) of the 2501a, and run clear ip ro * on both routers wait a couple of seconds, and run the sh ip ro command again (also on both routers) and post that too.

btw, did you add the static route on the cable router? if so, did you disable RIP on it?

I still have the felling Viper was correct when he said: "I'm pretty sure there's a simple mis-configuration somewhere."

Don't worry, you'll get it to work eventually.