static routing

Hi all,

Im currently studying through the Sybex 640-801 book by Todd Lammle,
re-reading through chapter 5 to set up a static route network.
Well I managed to setup the static routes on both my routers and I can ping from one router to the other, but I cant seem to be able to ping from host to serial interface.

To breifly explain what ive done so far, HostA has IP 192.168.10.2 ->this connects to RouterA ethernet0 (192.168.10.1) then I have a serial wan connection going from serial0 (192.168.30.1) to RouterB serial0(192.168.30.2). Then from RouterB ethernet 0 (192.168.20.1) I connect HostB (192.168.20.2).

From both routers I am able to ping each others' ethernet0 address.. and all other IP addresses in between., however I cant seem to ping the opposite end hosts. Or conversely eg: from hostA I cant ping RouterA's serial 0 address. and same goes for hostB situation.

What could I be doing wrong here?
what information should I be looking for to debug this?

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Comments

Nocturnal

Are your PCs plugged directly into the routers? If so, you need to use a crossover cable, not a straight through patch cable.

wildfire

you said host A cant ping routers a serial port what about its ether net port?

do you have Ip routring enabled?

have you set the gateway of last resort ie 0.0.0.0 0.0.0.0 x.x.x.x where x is the other router. on your host have you confirgure the defualt gateway? what subnet masks have you use? and what statci routes did you input?

netstat

Did u set the serial clock rates and bandwidth? also, did u specify which is the DCE and DTE?

check it out!

tunerX

HostA--E0-RouterA-S0--S0-RouterB-E0--HostB

HostA
Ip Address 192.168.10.2
Subnet mask 255.255.255.0
Default gateway 192.168.10.1

HostB
Ip Address 192.168.20.2
Subnet mask 255.255.255.0
Default gateway 192.168.20.1

RouterA
E0 - 192.168.10.1 255.255.255.0
S0 - 192.168.30.1 255.255.255.0

RouterB
E0 - 192.168.20.1 255.255.255.0
S0 - 192.168.30.2 255.255.255.0

RouterA config
configure terminal
ip routing
interface ethernet 0
ip address 192.168.10.1 255.255.255.0
no shut
interface serial 0
ip address 192.168.30.1 255.255.255.0
no shut
ip route 192.168.20.1 255.255.255.0 192.168.30.2
ip route 0.0.0.0 0.0.0.0 serial 0

RouterB config
configure terminal
ip routing
interface ethernet 0
ip address 192.168.20.1 255.255.255.0
no shut
interface serial 0
ip address 192.168.30.2 255.255.255.0
no shut
ip route 192.168.10.0 255.255.255.0 192.168.30.1
ip route 0.0.0.0 0.0.0.0 serial 0

If your config looks like this then it will work. The default route is optional. You said that HostA can ping all of RouterA's interfaces and HostB can ping all of RouterB's interfaces. If you still have trouble then it is either layer 1 or layer 2 between the routers or layer 3 on one, or both, of the hosts. If RouterA can ping RouterB then it is not layer 1, 2, or 3 on either of the routers.

Layer 1 on the router can be clocking or a bad cable.
Layer 2 on the router can be mismatched encapsulations.
Layer 3 on the hosts is the default gateway, subnet mask, and IP address.

fusebox

hehe,,, no no all cabling is checked out, because from my hosts, I can ping to the router's ethernet interface. Just cant seem to ping the serial interface that is closest to the host.

I'll paste in the results of show ip route;

Lab_A#show 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

192.168.30.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.30.2/32 is directly connected, Serial0
C 192.168.30.0/24 is directly connected, Serial0
C 192.168.10.0/24 is directly connected, Ethernet0
S 192.168.20.0/24 [1/0] via 192.168.30.2

and for RouterB

Lab_B#show 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

192.168.30.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.30.0/24 is directly connected, Serial0
C 192.168.30.1/32 is directly connected, Serial0
S 192.168.10.0/24 [1/0] via 192.168.30.1
C 192.168.20.0/24 is directly connected, Ethernet0

Could it be that these lines are causing problems? ie:
C 192.168.30.1/32 is directly connected, Serial0
C 192.168.30.2/32 is directly connected, Serial0

Basically, I did everything that TunerX mentioned, and then I also tried the default route command. I can ping all interfaces from one router to the others and vice versa, I just cant seem to ping from the host to the serial interface and beyond

I also have ip routing enabled.
Now could someone explain to me a little more on what Gateway of last resort means??

Also in windowsXP in TCP/IP properties, I added the network gateway address of 192.168.10.1 and 192.168.20.1 for RouterA and RouterB respectively. So that didnt help either.

oh and one more thing Im trying to setup a static network.

tunerX

post a show run from each router. You have something wierd going on.

fusebox

tunerX wrote:

post a show run from each router. You have something wierd going on.

Here is show run for RouterA;

Current configuration:
!
version 12.0
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname Lab_A
!
enable secret 5 $1$FI5P$ivxnlCo9m8QT3pAu9th5M.
!
!
!
!
!
ip subnet-zero
no ip domain-lookup
!
isdn voice-call-failure 0
!
!
!
interface Ethernet0
description This connects to Lab_A LAN
ip address 192.168.10.1 255.255.255.0
no ip directed-broadcast
!
interface Serial0
description Connects to Lab_B via WAN
ip address 192.168.30.1 255.255.255.0
no ip directed-broadcast
encapsulation ppp
no ip mroute-cache
no fair-queue
!
interface Serial1
no ip address
no ip directed-broadcast
shutdown
!
interface BRI0
no ip address
no ip directed-broadcast
shutdown
isdn guard-timer 0 on-expiry accept

!
router rip
version 2
network 192.168.0.0
network 192.168.22.0
!
ip classless
ip route 192.168.20.0 255.255.255.0 192.168.30.3
no ip http server
!
banner motd ^C This is the Lab_A router ^C
!
line con 0

password 7 070920455D0815
login
transport input none
line aux 0
password 7 070920455D0815
login
line vty 0 4
password 7 110F180C041307
login
!
end

for RouterB;

Current configuration:
!
version 12.0
no service pad
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname Lab_B
!
enable secret 5 $1$ZxK.$38F.St2QXGlhe2/kxlrCS/
enable password 7 141113021F0526
!
!
!
!
!
ip subnet-zero
no ip domain-lookup
!
isdn switch-type ntt
isdn voice-call-failure 0
!
!
!
interface Ethernet0
description This connects to Lab_B LAN
ip address 192.168.20.1 255.255.255.0
no ip directed-broadcast
no ip mroute-cache
no cdp enable
!
interface Serial0
description This connects to lab_A via WAN
ip address 192.168.30.2 255.255.255.0
no ip directed-broadcast
encapsulation ppp
no ip mroute-cache
clockrate 64000
no cdp enable
!
interface Serial1
no ip address
no ip directed-broadcast
no ip mroute-cache
shutdown
no cdp enable
!
interface BRI0
no ip address
no ip directed-broadcast
no ip mroute-cache
shutdown
isdn switch-type ntt
no cdp enable
!
ip classless
ip route 192.168.10.0 255.255.255.0 192.168.30.1
no ip http server
!
no cdp run
banner motd ^C This is Lab_B router ^C
!
line con 0
exec-timeout 0 0
password 7 045D0A0F1C2040
login
transport input none
no cdp enable
!
ip classless
ip route 192.168.10.0 255.255.255.0 192.168.30.1
no ip http server
!
no cdp run
banner motd ^C This is Lab_B router ^C
!
line con 0
exec-timeout 0 0
password 7 045D0A0F1C2040
login
transport input none
line aux 0
password 7 045D0A0F1C2040
login
line vty 0 4
password 7 045D0A0F1C2040
login
!
end

Okay I read up on default routing which addresses the gateway of last resort.
This shouldnt have anything to do with my network problem.

An interesting observation though is that in the book by Lammle, he doesnt get the student to verify that the hosts are communicating end to end. But rather what he does only is from RouterA he pings the ethernet 0 interface on RouterB and vice versa.... and having done this he claims that "since we can ping from end-to-end without a problem, our static route configuration was a success!".
Now I can do this, but I just wanted to test if I could ping from host to host and found I couldnt. After troubleshooting I found that my problem lies in that I cant ping from hostA to RouterA's serial0 [And same goes for HostB etc]

tunerX

Those configs look fine. What do you get when you traceroute from hostA to hostB, or hostB to hostA?

do a show interfaces serial 0 on both routers and post that info.

I would still say that there is something misconfigured on the hosts.

xetrev

tunerX wrote:

Those configs look fine. What do you get when you traceroute from hostA to hostB, or hostB to hostA?

do a show interfaces serial 0 on both routers and post that info.

I would still say that there is something misconfigured on the hosts.

make sure you have the default gateway set properly on your hosts. and if you have any firewall software on to turn it off

wildfire

just cusrious are one of you hosts connected to another network? or even worse to the internet via another interface?

if you are using windows 2000 or xp

go to the cmnd prompt

type

route add 192.168.X.X mask 255.255.255.0 192.168.Z.Z metric 1 IF Y

where x is the destination network adress

z the adjacent ethernet interface

y the interface number this forces it to use that interface

this will add a static route that will force packets destined for a network down one path.

I had a smililar problem becuase my machine was conneted to the internet and was sending broadcasts to my wirelless router

fusebox

Hi everyone,

After spending many hours today I finally got my static network to work

Basically I think the problem was that in windows when setting up a network such as the one I was trying you need to input the default gateway address correctly. In my case it was 192.168.10.1 and 192.168.20.1 ....... I wasnt too sure about this until I read the replies posted in this thread

But just changing this didnt work for me, I ended up starting from scratch and found that at times the only way to clear what I had was to reload the router (I had not saved the config file)

I must say that having your own equipment definitely gives you added experience in playing around with settings and configuratiosn etc. Money well spent even if I did have problems early on with my serial interfaces and IOS :P

xetrev

Hey dont get cought up on this one, i was trying to trunk two switches together with a regular cat5e cable. Turns out when trunking you need a crossover! Having the routers in front of you definently gives you a better feel for the IOS!