3.4.2.5 Packet Tracer - Troubleshooting Gre 442cs

Packet Tracer – Troubleshooting GRE Topology

Addressing Table Device

Interface

IP Address

Subnet Mask

Default Gateway

G0/0

172.31.0.1

255.255.255.0

N/A

S0/0/0

209.165.122.2

255.255.255.252

N/A

Tunnel 0

192.168.1.1

255.255.255.252

N/A

G0/0

172.31.1.1

255.255.255.0

N/A

S0/0/0

64.103.211.2

255.255.255.252

N/A

Tunnel 0

192.168.1.2

255.255.255.252

N/A

PC-A

NIC

172.31.0.2

255.255.255.0

172.31.0.1

PC-B

NIC

172.31.1.2

255.255.255.0

172.31.1.1

RA

RB

Objectives •

Find and Correct All Network Errors

•

Connectivity

Scenario A junior network was hired to set up a GRE tunnel between two sites and was unable to complete the task. You have been asked to correct configuration errors in the company network.

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Packet Tracer – Troubleshooting GRE

Part 1: Find and Correct All Network Errors. Device

Error

Correction

RA

G0/0 IP Address Incorrect

RA(config)#interface g0/0 RA(config-if)#no ip address RA(config-if)#ip address 172.31.0.1 255.255.255.0

RA

Tunnel 0 IP Address Incorrect:

RA(config)#interface tunnel 0 RA(config-if)#no ip address RA(config-if)#ip address 192.168.1.1 255.255.255.252

interface Tunnel0 ip address 172.31.0.1 255.255.255.0

RB

Tunnel 0 configured with wrong Source Interface and wrong destination IP Address:

tunnel source GigabitEthernet0/0 tunnel destination 192.168.1.1

RA

Ip route next hop incorrect:

ip route 172.31.1.0 255.255.255.0 64.103.211.2

RA#show run Building configuration... Current configuration : 1048 bytes version 15.1 no service timestamps log datetime msec no service timestamps debug datetime msec no service -encryption hostname RA ip cef no ipv6 cef license udi pid CISCO2911/K9 sn FTX15242579 spanning-tree mode pvst

interface Tunnel0

RB(config)#interface tunnel 0 RB(config-if)#no tunnel source g0/0 RB(config-if)#no tunnel destination 192.168.1.1 RB(config-if)#tunnel source s0/0/0 RB(config-if)#tunnel destination 209.165.122.2

RA(config)#no ip route 172.31.1.0 255.255.255.0 64.103.211.2 RA(config)#ip route 172.31.1.0 255.255.255.0 192.168.1.2

ip address 192.168.1.1 255.255.255.252 mtu 1476 tunnel source Serial0/0/0 tunnel destination 64.103.211.2 interface GigabitEthernet0/0 ip address 172.31.0.1 255.255.255.0 duplex auto speed auto interface GigabitEthernet0/1 no ip address duplex auto speed auto shutdown interface GigabitEthernet0/2 no ip address duplex auto speed auto shutdown interface Serial0/0/0 ip address 209.165.122.2 255.255.255.252 interface Serial0/0/1 no ip address clock rate 2000000 shutdown interface Vlan1 no ip address shutdown ip classless ip route 0.0.0.0 0.0.0.0 Serial0/0/0 ip route 172.31.1.0 255.255.255.0 192.168.1.2 ip flow-export version 9 line con 0 line aux 0 line vty 0 4 end

RB#show run

Building configuration... Current configuration : 1048 bytes version 15.1 no service timestamps log datetime msec no service timestamps debug datetime msec no service -encryption hostname RB ip cef no ipv6 cef license udi pid CISCO2911/K9 sn FTX152497Z4 spanning-tree mode pvst interface Tunnel0 ip address 192.168.1.2 255.255.255.252 mtu 1476 tunnel source Serial0/0/0 tunnel destination 209.165.122.2 interface GigabitEthernet0/0 ip address 172.31.1.1 255.255.255.0 duplex auto speed auto interface GigabitEthernet0/1 no ip address duplex auto speed auto shutdown interface GigabitEthernet0/2 no ip address duplex auto speed auto shutdown interface Serial0/0/0 ip address 64.103.211.2 255.255.255.252 interface Serial0/0/1 no ip address clock rate 2000000 shutdown interface Vlan1 no ip address shutdown ip classless ip route 0.0.0.0 0.0.0.0 Serial0/0/0 ip route 172.31.0.0 255.255.255.0 192.168.1.1 ip flow-export version 9

line con 0 line aux 0 line vty 0 4 end

Part 2: Connectivity Step 1: Ping PCA from PCB. Attempt to ping the IP address of PCA from PCB. The ping should be successful.

C:\>ping 172.31.0.2 Pinging 172.31.0.2 with 32 bytes of data: Request timed out. Reply from 172.31.0.2: bytes=32 time=2ms TTL=126 Reply from 172.31.0.2: bytes=32 time=22ms TTL=126 Reply from 172.31.0.2: bytes=32 time=3ms TTL=126 Ping statistics for 172.31.0.2: Packets: Sent = 4, Received = 3, Lost = 1 (25% loss), Approximate round trip times in milli-seconds: Minimum = 2ms, Maximum = 22ms, Average = 9ms Step 2: Trace the path from PCA to PCB. Attempt to trace the path from PCA to PCB. Note the lack of public IP addresses in the output.

Tracing route to 172.31.1.2 over a maximum of 30 hops: 1 2 3

0 ms 2 ms 10 ms

14 ms 15 ms 12 ms

0 ms 19 ms 14 ms

172.31.0.1 192.168.1.2 172.31.1.2

Trace complete.

© 2017 Cisco and/or its s. All rights reserved. This document is Cisco Public.

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