Need Help!! MS Loopback

Hello everyone...

I trying to connect my PC loopback adapter to GNS3 router...the topology is 5 routers & SW:
R1>R2 (WAN 172.16.80.0/24)
R2>R3 (WAN 172.16.40.0/24)
R3>R4 (WAN 172.16.20.0/24)
R4>SW>R5 (LAN 172.16.10.0/24)
using OSPF RP area 0,, all works fine, I can ping every interface from anywhere..

I connect my PC loopback interface to R1 with network 172.16.70.0/24 and the adapter parameters are:
IP/mask 172.16.70.2/24
GW/DNS 172.16.70.1 which is R1 fa 0/0
I can ping to/from R1 also I'm able to run SDM from my PC to R1, but the problem is I cannot ping any router except R1 from PC!!
also it seems like none of the routers can see my PC, but they can ping the gateway 172.16.70.1

any ideas pleaseeeeeeee?? I really spent alot of time on this trying to figure out WHERE IS THE PROBLEM!!!

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Comments

drkat

can you post config? can you ping the PC from any other interface? is your routing all set?

Amjo

!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
ip cef
!
!
!
!
ip auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
!
multilink bundle-name authenticated
!
!
!
username amjo password 0 cisco
archive
log config
hidekeys
!

interface FastEthernet0/0
ip address 172.16.70.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0
ip address 172.16.80.2 255.255.255.0
clock rate 2000000
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/1
no ip address
shutdown
clock rate 2000000
!
interface FastEthernet2/0
!
interface FastEthernet2/1
!
interface FastEthernet2/2
!
interface FastEthernet2/3
!
interface FastEthernet2/4
...
!
interface FastEthernet2/10
!
interface FastEthernet2/11
!

interface Vlan1
no ip address
!
ip forward-protocol nd
!
!
ip http server
no ip http secure-server
!
!
!
!
!
!
!
control-plane
!
!
line con 0
line aux 0
line vty 0 4
password cisco
login
line vty 5 903
password cisco
login
!
!
end

###################
I cannot ping the PC from any where except R1>

all the routes in,, using ospf.... all the routers can ping my subnet ip 172.16.70.1 but they cannot ping 172.16.70.2>>>>> the route 70/24 is in the routing table of all routers

alan2308

Does your PC have a route to the networks in the GNS3 topology? In order for a ping to work, it has to be able to reach the remote host. R1 is reachable because it is on the same network as your PC.

Amjo

alan2308 wrote: »

Does your PC have a route to the networks in the GNS3 topology? In order for a ping to work, it has to be able to reach the remote host. R1 is reachable because it is on the same network as your PC.

Yep, I already add the interface to the ospf area 0 and its shwon up in the routing table of all routers....!!

even I turned the firewall off known that it could be the problem but no luck..

really I need to access the GNS work from my pc in order to be able to run my virtualbox replacing the "Qemu microcore hosts" and have more flexibility to be in a real world...

alan2308

Amjo wrote: »

Yep, I already add the interface to the ospf area 0 and its shwon up in the routing table of all routers....!!

That's not what I mean. The GNS3 routers do need a route to the network that the PC lives on, but the PC also needs a route back to the GNS3 routers.

networker050184

alan2308 wrote: »

That's not what I mean. The GNS3 routers do need a route to the network that the PC lives on, but the PC also needs a route back to the GNS3 routers.

This was my first thought as well. Probably have another interface up and sending the traffic out that default gateway.

Amjo

Finally it works woooow.. thanks alan
I add a route on my PC to the existing network and it works just fine ... plus turn off windows/Avast firewalls
but I notice that there was an existent route in the PC (default route) to 0.0.0.0 0.0.0.0 through the the same gateway (R1 fa0/0)..
why it doesn't take that route to the entire network hummm!!