Ping Schming

Hi everyone,

Small doubtz. What usually the cause if Im able to ping one side of a router but not the other? Ive attached the topo here...

Router B has a NAT on its inside(Fa0/0) that translates the IP adds of the PC1, PC2(both 192.168.100.x) and SRV001(192.168.101.x)...

For all three the translation happens but only PC1,2 cant ping Int_host while SRV001 can!

Any advise on how to troubleshoot this?

Thanks lot in advance!!!

Topo.jpg

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Comments

apd123

There is no usual cause could be natting, acl, routing etc. Post the configs and then we will all know the cause.

Dubuku57

Hi, here are the configs for Routers B and ISP. Its running in packettracer, i hope it doesnt turn out to be a bug...Thank you!

RouterB#sh run
Building configuration...

Current configuration : 1134 bytes
!
version 12.2
no service password-encryption
!
hostname RouterB
!
!
!
!
!
ip ssh version 1
!
!
interface FastEthernet0/0
ip address 192.168.101.2 255.255.255.0
ip nat inside
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface FastEthernet1/0
no ip address
duplex auto
speed auto
shutdown
!
interface FastEthernet1/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial1/0
ip address 52.2.2.2 255.255.255.248
ip nat outside
clock rate 64000
!
interface Serial1/1
no ip address
shutdown
!
interface Serial1/2
no ip address
shutdown
!
interface Serial1/3
no ip address
shutdown
!
ip nat pool Nithya 200.5.22.19 200.5.22.22 netmask 255.255.255.248
ip nat inside source list 1 pool Nithya overload
ip classless
ip route 192.168.100.0 255.255.255.248 192.168.101.1
ip route 0.0.0.0 0.0.0.0 52.2.2.1
ip route 200.2.2.0 255.255.255.0 52.2.2.1
!
!
access-list 1 permit 192.168.100.0 0.0.0.7
access-list 1 permit 192.168.101.0 0.0.0.7
access-list 1 permit 192.168.96.0 0.0.7.255
!
!
!
line con 0
logging synchronous
line vty 0 4
login
!
!
end

ISP#sh run
Building configuration...

Current configuration : 735 bytes
!
version 12.2
no service password-encryption
!
hostname ISP
!
!
!
!
!
ip ssh version 1
!
!
interface FastEthernet0/0
ip address 200.2.2.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface FastEthernet1/0
no ip address
duplex auto
speed auto
shutdown
!
interface FastEthernet1/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial1/0
ip address 52.2.2.1 255.255.255.248
!
interface Serial1/1
no ip address
shutdown
!
interface Serial1/2
no ip address
shutdown
!
interface Serial1/3
no ip address
shutdown
!
ip classless
ip route 0.0.0.0 0.0.0.0 Serial1/0
!
!
!
!
!
line con 0
logging synchronous
line vty 0 4
login
!
!
end

sandman748

What is router A's config?

I'm also assuming that you're hosts have the last octet of the ip address between 2-6

Edit: I'm starting to think my questions are irrelevant, but I cant figure it out.

Dubuku57

Here you go, sorry missed it out...

RouterA#sh run
Building configuration...

Current configuration : 790 bytes
!
version 12.2
no service password-encryption
!
hostname RouterA
!
!
!
!
!
ip ssh version 1
!
!
interface FastEthernet0/0
ip address 192.168.100.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 192.168.101.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet1/0
no ip address
duplex auto
speed auto
shutdown
!
interface FastEthernet1/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial1/0
no ip address
shutdown
!
interface Serial1/1
no ip address
shutdown
!
interface Serial1/2
no ip address
shutdown
!
interface Serial1/3
no ip address
shutdown
!
ip classless
ip route 192.168.101.0 255.255.255.0 192.168.101.2
ip route 52.2.2.0 255.255.255.248 192.168.101.2
!
!
!
!
!
line con 0
line vty 0 4
login
!
!
end

Yes the hosts are:
PC1: 192.168.100.2/24 , DG: 192.168.100.1
PC2: 192.168.100.3/24, DG : 192.168.100.1
SVR001: 192.168.101.3/24, DG: 192.168.101.2
Int_Host: 200.2.2.2/24, DG: 200.2.2.1

Any ideas..?

sandman748

The problem is on router A. You either need to have an ip route to the 200. network your trying to route to, or a default route to router B when no routes are matched (i.e. 0.0.0.0 0.0.0.0 192.168.101.2). It would make more sense to have the default route to router B as you wouldnt have a whole bunch of static routes to networks that your ISP is connecting you to.

Edit: I just saw the you put a static route on B to the 200. network as well. As I said above you would not need that route. The default route you created above it would forward out to the ISP. Think of all the static routes you would have if you had to do that for every network on the internet.

Dubuku57

Oh man..cant believe its that simple, yeah it works...and i was staring at these configs for so long..

Thanks guys!!!