Topology Overview (Actual Troubleshooting lab design is for below network design)
Client Should have IP 10.2.1.3
EIGRP 100 is running between switch DSW1 & DSW2
OSPF (Process ID 1) is running between R1, R2, R3, R4
Network of OSPF is redistributed in EIGRP
BGP 65001 is configured on R1 with Webserver cloud AS 65002
HSRP is running between DSW1 & DSW2 Switches
The company has created the test bed shown in the layer 2 and layer 3 topology exhibits.
This network consists of four routers, two layer 3 switches and two layer 2 switches.
In the IPv4 layer 3 topology, R1, R2, R3, and R4 are running OSPF with an OSPF process number 1.
DSW1, DSW2 and R4 are running EIGRP with an AS of 10. Redistribution is enabled where
necessary.
R1 is running a BGP AS with a number of 65001. This AS has an eBGP connection to AS 65002
in the ISP’s network. Because the company’s address space is in the private range.
R1 is also providing NAT translations between the inside (10.1.0.0/16 & 10.2.0.0/16) networks and
outside (209.65.0.0/24) network.
ASW1 and ASW2 are layer 2 switches.
NTP is enabled on all devices with 209.65.200.226 serving as the master clock source.
The client workstations receive their IP address and default gateway via R4’s DHCP server.
The default gateway address of 10.2.1.254 is the IP address of HSRP group 10 which is running
on DSW1 and DSW2.
In the IPv6 layer 3 topology R1, R2, and R3 are running OSPFv3 with an OSPF process number
6.
DSW1, DSW2 and R4 are running RIPng process name RIP_ZONE.
The two IPv6 routing domains, OSPF 6 and RIPng are connected via GRE tunnel running over the
underlying IPv4 OSPF domain. Redistrution is enabled where necessary.
Recently the implementation group has been using the test bed to do a ‘proof-of-concept’ on
several implementations. This involved changing the configuration on one or more of the devices.
You will be presented with a series of trouble tickets related to issues introduced during these
configurations.
Note: Although trouble tickets have many similar fault indications, each ticket has its own issue
and solution.
Each ticket has 3 sub questions that need to be answered & topology remains same.
Question-1Fault is found on which device,
Question-2Fault condition is related to,
Question-3What exact problem is seen & what needs to be done for solution
===========================================
Solution
Steps need to follow as below:
When we check on client 1 & Client 2 desktop we are not receiving DHCP address from R4
ipconfig —– Client will be receiving IP address 10.2.1.3
From Client PC we can ping 10.2.1.254….
But IP 10.2.1.3 is able to ping from R4, R3, R2, R1.
Since the problem is R1 (2026::111:1) is not able to ping loopback of DSW1 (2026::102:1).
Kindly check for neighbourship of routers as IPV6…. As per design below neighbourship should
be present for IPV6
R1 —R2 — R3 — R4— DSW1 & DSW2 —– Neighbourship between devices of IPV6
R2 IPV6 OSPF neighbourship is with R1
R3 IPV6 OSPF neighbourship is with R4
As per above snapshot we cannot see IPV6 neighbourship between R2 & R3 when checked
interface configuration ipv6 ospf area 0 is missing on R2 which is connected to R3
Change required:On R2, IPV6 OSPF routing, Configuration is required ipv6 ospf 6 area 0
under interface serial 0/0/0.23
————————————————-
So in ticket Answer to the fault condition will be as below for:
The implementations group has been using the test bed to do a ‘proof-of-concept’. After
several changes to the network addressing, routing schemes, a trouble ticket has been
opened indicating that the loopback address on R1 (2026::111:1) is not able to ping the
loopback address on DSW2(2026::102:1).
Use the supported commands to isolated the cause of this fault and answer the following
questions.
What is the solution to fault condition?
A.
Under the interface Serial 0/0/0.23 configuration enter the ipv6 ospf 6 area 0 command.
B.
Under the interface Serial0/0/0.12 configuration enter the ipv6 ospf 6 area 12 command.
C.
Under ipv6 router ospf 6 configuration enter the network 2026::1:/122 area 0 command.
D.
Under ipv6 router ospf 6 configuration enter no passive-interface default command.