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This section presents a trouble ticket based on an IPv6 and OSPF configuration. You are
given sample show command output and are challenged to identify a resolution for the issue
described.
Trouble Ticket #11
You receive the following trouble ticket:
Company A recently added IPv6 addressing to its existing IPv4 addressing. OSPFv3
is the protocol being used to route the IPv6 traffic.
Although the configuration was originally functional, now several OSPFv3 adjacencies
are not forming. Full IPv6 reachability throughout the topology needs to be established.
This trouble ticket references the topology shown in Figure 12-6.
S 1/0.2
.1
Lo 0
10.3.3.3/32 .1
Fa 0/0
S 1/0.2
.1
DLCI = 182
DLCI = 811
S 1/0.1
.1
Lo 0
10.1.1.1/32
Lo 0
10.2.2.2/32
172.16.1.0/30
Fa 0/0
DLCI = 881
.11
FXS
1/0/0
FXS
1/0/1
R2
192.168.0.0/24
Fa 0/1
.11
172.16.2.0/30
S 1/0.1
.2
DLCI = 882
Fa 0/0
.22
10.1.3.0/30
10.1.2.0/24
Gig 0/8 Fa 5/46
Lo 0
10.4.4.4/32
S 1/0.2
.2
DLCI = 821 .2
Fa 0/0
Gig 0/9 Fa 5/47
Fa 5/45
x3333
Gig 0/10 Fa 5/48
100 Mbps
10 Mbps
R1
BB2
BB1
R2 FRSW
x2222
OSPF Area 1 OSPF Area 0
x1111
SW1 SW2
S 1/0.1
.2
DLCI = 181
A:A:A:A::X/64
192.168.1.0/24
B:B:B:B::X/64
D:D:D:D::X/64
C:C:C:C::X/64
E:E:E:E::X/64
F:F:F:F::X/64
Figure 12-6 Trouble Ticket #11 Topology
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Viewing Baseline Information
The routers in the topology were similarly configured for IPv6 and OSPFv3. The show run
command was issued on router R2, the output of which is provided in Example 12-5. The
configuration on the other routers in the topology was consistent with the configuration
shown for router R2.
Example 12-5 Working Configuration on Router R2
R2# show run
Building configuration...
hostname R2
--- OUTPUT OMITTED ---
!
ipv6 unicast-routing
ipv6 cef
!
interface Loopback0
ip address 10.2.2.2 255.255.255.255
!
interface FastEthernet0/0
ip address 192.168.0.22 255.255.255.0
ipv6 address B:B:B:B::22/64
ipv6 ospf 1 area 1
!
interface Serial1/0.1 point-to-point
ip address 172.16.1.2 255.255.255.252
ipv6 address C:C:C:C::2/64
ipv6 ospf 1 area 0
frame-relay interface-dlci 181
!
interface Serial1/0.2 point-to-point
ip address 172.16.2.1 255.255.255.252
ipv6 address D:D:D:D::1/64
ipv6 ospf 1 area 0
frame-relay interface-dlci 182
!
!
--- OUTPUT OMITTED ---
ipv6 router ospf 1
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Originally, all routers had full reachability throughout the topology, as verified in
Examples 12-6, 12-7, 12-8, and 12-9.
Example 12-6 Router R1’s Initial IPv6 Routing Table
R1# show ipv6 route
IPv6 Routing Table - 10 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
U - Per-user Static route
I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
C A:A:A:A::/64 [0/0]
via ::, FastEthernet0/0
L A:A:A:A::11/128 [0/0]
via ::, FastEthernet0/0
C B:B:B:B::/64 [0/0]
via ::, FastEthernet0/1
L B:B:B:B::11/128 [0/0]
via ::, FastEthernet0/1
OI C:C:C:C::/64 [110/65]
via FE80::C201:8FF:FE2C:0, FastEthernet0/1
OI D:D:D:D::/64 [110/65]
via FE80::C201:8FF:FE2C:0, FastEthernet0/1
OI E:E:E:E::/64 [110/129]
via FE80::C201:8FF:FE2C:0, FastEthernet0/1
OI F:F:F:F::/64 [110/75]
via FE80::C201:8FF:FE2C:0, FastEthernet0/1
L FE80::/10 [0/0]
via ::, Null0
L FF00::/8 [0/0]
via ::, Null0
Example 12-7 Router R2’s Initial IPv6 Routing Table
R2# show ipv6 route
IPv6 Routing Table - 11 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
U - Per-user Static route
I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
O A:A:A:A::/64 [110/11]
via FE80::209:B7FF:FEFA:D1E1, FastEthernet0/0
C B:B:B:B::/64 [0/0]
via ::, FastEthernet0/0
L B:B:B:B::22/128 [0/0]
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via ::, FastEthernet0/0
C C:C:C:C::/64 [0/0]
via ::, Serial1/0.1
L C:C:C:C::2/128 [0/0]
via ::, Serial1/0.1
C D:D:D:D::/64 [0/0]
via ::, Serial1/0.2
L D:D:D:D::1/128 [0/0]
via ::, Serial1/0.2
O E:E:E:E::/64 [110/128]
via FE80::C202:8FF:FE98:0, Serial1/0.1
via FE80::C200:8FF:FE2C:0, Serial1/0.2
O F:F:F:F::/64 [110/74]
via FE80::C202:8FF:FE98:0, Serial1/0.1
via FE80::C200:8FF:FE2C:0, Serial1/0.2
L FE80::/10 [0/0]
via ::, Null0
L FF00::/8 [0/0]
via ::, Null0
Example 12-8 Router BB1’s Initial IPv6 Routing Table
BB1# show ipv6 route
IPv6 Routing Table - 11 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
U - Per-user Static route
I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
OI A:A:A:A::/64 [110/75]
via FE80::C201:8FF:FE2C:0, Serial1/0.2
OI B:B:B:B::/64 [110/74]
via FE80::C201:8FF:FE2C:0, Serial1/0.2
C C:C:C:C::/64 [0/0]
via ::, Serial1/0.2
L C:C:C:C::1/128 [0/0]
via ::, Serial1/0.2
O D:D:D:D::/64 [110/74]
via FE80::C200:8FF:FE2C:0, FastEthernet0/0
C E:E:E:E::/64 [0/0]
via ::, Serial1/0.1
L E:E:E:E::1/128 [0/0]
via ::, Serial1/0.1
C F:F:F:F::/64 [0/0]
via ::, FastEthernet0/0
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L F:F:F:F::1/128 [0/0]
via ::, FastEthernet0/0
L FE80::/10 [0/0]
via ::, Null0
L FF00::/8 [0/0]
via ::, Null0
Example 12-9 Router BB2’s Initial IPv6 Routing Table
BB2# show ipv6 route
IPv6 Routing Table - 11 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
U - Per-user Static route
I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
OI A:A:A:A::/64 [110/75]
via FE80::C201:8FF:FE2C:0, Serial1/0.2
OI B:B:B:B::/64 [110/74]
via FE80::C201:8FF:FE2C:0, Serial1/0.2
O C:C:C:C::/64 [110/74]
via FE80::C202:8FF:FE98:0, FastEthernet0/0
C D:D:D:D::/64 [0/0]
via ::, Serial1/0.2
L D:D:D:D::2/128 [0/0]
via ::, Serial1/0.2
C E:E:E:E::/64 [0/0]
via ::, Serial1/0.1
L E:E:E:E::2/128 [0/0]
via ::, Serial1/0.1
C F:F:F:F::/64 [0/0]
via ::, FastEthernet0/0
L F:F:F:F::2/128 [0/0]
via ::, FastEthernet0/0
L FE80::/10 [0/0]
via ::, Null0
L FF00::/8 [0/0]
via ::, Null0
Example 12-10 provides an additional sampling of baseline verification commands issued
on router R2.
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Example 12-10 Additional Baseline Verification Commands on Router R2
R2# show ipv6 ospf interface serial 1/0.2
Serial1/0.2 is up, line protocol is up
Link Local Address FE80::C201:8FF:FE2C:0, Interface ID 14
Area 0, Process ID 1, Instance ID 0, Router ID 10.2.2.2
Network Type POINT_TO_POINT, Cost: 64
Transmit Delay is 1 sec, State POINT_TO_POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:04
Index 1/2/3, flood queue length 0
Next 0x0(0)/0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 2
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 10.4.4.4
Suppress hello for 0 neighbor(s)
R2# show ipv6 ospf
Routing Process “ospfv3 1” with ID 10.2.2.2
It is an area border router
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
LSA group pacing timer 240 secs
Interface flood pacing timer 33 msecs
Retransmission pacing timer 66 msecs
Number of external LSA 0. Checksum Sum 0x000000
Number of areas in this router is 2. 2 normal 0 stub 0 nssa
Reference bandwidth unit is 100 mbps
Area BACKBONE(0)
Number of interfaces in this area is 2
SPF algorithm executed 8 times
Number of LSA 14. Checksum Sum 0x063F6C
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
Area 1
Number of interfaces in this area is 1
SPF algorithm executed 5 times
Number of LSA 11. Checksum Sum 0x0481E4
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
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Flood list length 0
R2# show ipv6 ospf neighbor
Neighbor ID Pri State Dead Time Interface ID Interface
10.4.4.4 1 FULL/ - 00:00:36 14 Serial1/0.2
10.3.3.3 1 FULL/ - 00:00:36 14 Serial1/0.1
10.1.1.1 1 FULL/BDR 00:00:39 4 FastEthernet0/0
Troubleshoot and Resolve the Identified OSPFv3 Adjacency Issue
The trouble ticket indicates that several adjacencies are not being formed. So, you decide
to start your troubleshooting efforts on router R1 and check its adjacency with router R2,
and then check the adjacencies between R2 and BB1 and BB2. Finally, you will check the
adjacencies between BB1 and BB2.
Issue #1: Adjacency Between Routers R1 and R2
Example 12-11 shows the data collected from router R1.
Example 12-11 Troubleshooting Data Collection on Router R1
R1# show ipv6 ospf neighbor
R1# debug ipv6 ospf adj
OSPFv3 adjacency events debugging is on
R1# debug ipv6 ospf hello
OSPFv3 hello events debugging is on
R1# u all
All possible debugging has been turned off
R1# show run
...OUTPUT OMITTED...
hostname R1
!
ipv6 unicast-routing
ipv6 cef
!
interface Loopback0
ip address 10.1.1.1 255.255.255.255
!
interface FastEthernet0/0
ip address 192.168.1.11 255.255.255.0
ipv6 address A:A:A:A::11/64
ipv6 ospf 100 area 1
!
interface FastEthernet0/1
ip address 192.168.0.11 255.255.255.0
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ipv6 address B:B:B:B::11/64
ipv6 ospf 100 area 1
!
ipv6 router ospf 100
...OUTPUT OMITTED...
R1# show ipv6 ospf interface fa 0/1
FastEthernet0/1 is up, line protocol is up
Link Local Address FE80::209:B7FF:FEFA:D1E1, Interface ID 4
Area 1, Process ID 100, Instance ID 0, Router ID 192.168.1.11
Network Type BROADCAST, Cost: 1
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 192.168.1.11, local address FE80::209:B7FF:FEFA:D1E1
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:03
Index 1/2/2, flood queue length 0
Next 0x0(0)/0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 2
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Notice that router R1 has not formed an adjacency with router R2. Therefore, as a first
step in your troubleshooting efforts, you attempt to resolve the issue by preventing
routers R1 and R2 from forming an adjacency. Example 12-12 shows the data collected
from router R2.
Example 12-12 Troubleshooting Data Collection on Router R2
R2# show ipv6 ospf neighbor
R2# debug ipv6 ospf adj
OSPFv3 adjacency events debugging is on
R2# u all
All possible debugging has been turned off
R2# show run
...OUTPUT OMITTED...
hostname R2
!
ipv6 unicast-routing
ipv6 cef
!
interface Loopback0
ip address 10.2.2.2 255.255.255.255
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!
interface FastEthernet0/0
ip address 192.168.0.22 255.255.255.0
ipv6 address B:B:B:B::22/64
ipv6 ospf hello-interval 60
ipv6 ospf 1 area 1
!
interface Serial1/0
no ip address
encapsulation frame-relay
!
interface Serial1/0.1 point-to-point
ip address 172.16.1.2 255.255.255.252
ipv6 address C:C:C:C::2/64
ipv6 ospf 1 area 0
frame-relay interface-dlci 181
!
interface Serial1/0.2 point-to-point
ip address 172.16.2.1 255.255.255.252
ipv6 address D:D:D:D::1/64
ipv6 ospf network point-to-multipoint
ipv6 ospf 1 area 0
frame-relay interface-dlci 182
!
ipv6 router ospf 1
passive-interface default
...OUTPUT OMITTED...
Based on the output provided in Examples 12-11 and 12-12, hypothesize why routers R1
and R2 are not forming an adjacency. On a separate sheet of paper, write out your suggested
solution to correct the issue.
Issue #1: Suggested Solution
Notice in Example 12-12 that router R2’s HELLO timer on the Fast Ethernet 0/0 interface
was set to a non-default value, whereas the other end of the link was still set to the default.
Also, router R2 had its OSPFv3 process configured with the passive-interface default
command, which prevented any of router R2’s interfaces from forming OSPFv3 adjacencies.
Example 12-13 shows the correction of these configuration issues on router R2.
Example 12-13 Correcting Router R2’s HELLO Timer and Passive-Interface
Configuration
R2# conf term
Enter configuration commands, one per line. End with CNTL/Z.
R2(config)# int fa 0/0
R2(config-if)# no ipv6 ospf hello-interval 60
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R2(config-if)# exit
R2(config)# ipv6 router ospf 1
R2(config-rtr)# no passive-interface default
Issue #2: Adjacency Between Routers R2 and BB2
After implementing the fix shown in Example 12-13, router R2 successfully forms OSPF
adjacencies with routers R1 and BB1. However, an adjacency is not successfully formed
with router BB2. Example 12-14 shows the output of the show ipv6 ospf interface s1/0.2
command issued on router BB2. This command was issued to view the OSPFv3 configuration
of router BB2’s Serial 1/0.2 subinterface, which is the subinterface used to connect to
router R2.
Example 12-14 Viewing Router BB2’s OSPFv3 Configuration on Subinterface Serial
1/0.2
BB2# show ipv6 ospf interface s1/0.2
Serial1/0.2 is up, line protocol is up
Link Local Address FE80::C200:8FF:FE2C:0, Interface ID 14
Area 0, Process ID 1, Instance ID 0, Router ID 10.4.4.4
Network Type POINT_TO_POINT, Cost: 64
Transmit Delay is 1 sec, State POINT_TO_POINT,
R2# show ipv6 ospf neighbor
R2# debug ipv6 ospf adj
OSPFv3 adjacency events debugging is on
R2# u all
All possible debugging has been turned off
R2# show run
...OUTPUT OMITTED...
hostname R2
!
ipv6 unicast-routing
ipv6 cef
!
interface Loopback0
ip address 10.2.2.2 255.255.255.255
!
interface FastEthernet0/0
ip address 192.168.0.22 255.255.255.0
ipv6 address B:B:B:B::22/64
ipv6 ospf hello-interval 60
ipv6 ospf 1 area 1
!
interface Serial1/0
no ip address
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encapsulation frame-relay
!
interface Serial1/0.1 point-to-point
ip address 172.16.1.2 255.255.255.252
ipv6 address C:C:C:C::2/64
ipv6 ospf 1 area 0
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:08
Index 1/3/3, flood queue length 0
Next 0x0(0)/0x0(0)/0x0(0)
Last flood scan length is 2, maximum is 2
Last flood scan time is 0 msec, maximum is 4 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Based on router R2’s configuration (shown in Example 12-12) and the output shown in
Example 12-14, determine why an OSPF adjacency is not being formed between routers
R2 and BB2. Again, on a separate sheet of paper, write out your suggested solution.
Issue #2: Suggested Solution
Router R2’s OSPF network type on subinterface Serial 1/0.2 was set to point-to-multipoint,
while the other end of the link was the default network type of point-to-point.
Example 12-15 shows the correction of router R2’s misconfiguration.
Example 12-15 Correcting Router R2’s OSPF Network Type
R2# conf term
Enter configuration commands, one per line. End with CNTL/Z.
R2(config)# int s1/0.2
R2(config-subif)# no ipv6 ospf network point-to-multipoint
R2(config-subif)# exit
At this point in the troubleshooting process, routers R1 and R2 have formed adjacencies.
Additionally, router R2 has formed adjacencies with routers BB1 and BB2. The output in
Example 12-16 confirms the establishment of these adjacencies.
Example 12-16 Confirming Router R2’s OSPF Adjacencies
R2# show ipv6 ospf neighbor
Neighbor ID Pri State Dead Time Interface ID Interface
10.4.4.4 1 FULL/ - 00:00:36 14 Serial1/0.2
10.3.3.3 1 FULL/ - 00:00:36 14 Serial1/0.1
192.168.1.11 1 FULL/DR 00:00:39 4 FastEthernet0/0
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Issue #3: Adjacency Between Routers BB1 and BB2
As seen in the output provided in Example 12-17, router BB1 has formed an adjacency
with router BB2 over router BB1’s Fast Ethernet 0/0 interface. However, an adjacency has
not been successfully formed with router BB2 over router BB1’s Serial 1/0.1 subinterface.
Example 12-17 Determining Router BB1’s Adjacencies
To investigate why an OSPF adjacency is not forming with router BB2 via router BB1’s Serial
1/0.1 subinterface, the debug ipv6 ospf adj and debug ipv6 ospf hello commands were
issued on router BB1, as seen in Example 12-18.
Example 12-18 Debugging OSPFv3 Adjacency and Hello Events on Router BB1
BB1# debug ipv6 ospf adj
OSPFv3 adjacency events debugging is on
BB1# debug ipv6 ospf hello
OSPFv3 hello events debugging is on
BB1#
*Mar 1 00:19:24.707: OSPFv3: Rcv DBD from 10.4.4.4 on Serial1/0.1 seq 0x1AEF opt
0x0013 flag 0x7 len 28 mtu 1500 state EXSTART
*Mar 1 00:19:24.707: OSPFv3: Nbr 10.4.4.4 has larger interface MTU
*Mar 1 00:19:25.015: OSPFv3: Rcv hello from 10.2.2.2 area 0 from Serial1/0.2
FE80::C201:8FF:FE2C:0 interface ID 13
*Mar 1 00:19:25.019: OSPFv3: End of hello processing
*Mar 1 00:19:28.583: OSPFv3: Send hello to FF02::5 area 0 on Serial1/0.2 from
FE80::C202:8FF:FE98:0 interface ID 14
*Mar 1 00:19:28.647: OSPFv3: Rcv hello from 10.4.4.4 area 0 from Serial1/0.1
FE80::C200:8FF:FE2C:0 interface ID 13
*Mar 1 00:19:28.651: OSPFv3: End of hello processing
*Mar 1 00:19:28.983: OSPFv3: Send hello to FF02::5 area 0 on FastEthernet0/0
from FE80::C202:8FF:FE98:0 interface ID 4
*Mar 1 00:19:29.215: OSPFv3: Rcv hello from 10.4.4.4 area 0 from FastEthernet0/0
FE80::C200:8FF:FE2C:0 interface ID 4
*Mar 1 00:19:29.219: OSPFv3: End of hello processing
BB1# u all
All possible debugging has been turned off
BB1# show ipv6 ospf neigh
Neighbor ID Pri State Dead Time Interface ID Interface
10.2.2.2 1 FULL/ - 00:00:37 13 Serial1/0.2
10.4.4.4 1 DOWN/ - - 13 Serial1/0.1
10.4.4.4 1 FULL/DR 00:00:34 4 FastEthernet0/0
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Because your troubleshooting on router BB1 is focused on BB1’s Serial 1/0.1 subinterface,
the show ipv6 interface s1/0.1 command was issued, the output for which appears in
Example 12-19.
Example 12-19 Viewing the IPv6 Configuration on Router BB1’s Serial 1/0.1
Subinterface
BB1# show ipv6 interface s1/0.1
Serial1/0.1 is up, line protocol is up
IPv6 is enabled, link-local address is FE80::C202:8FF:FE98:0
Global unicast address(es):
E:E:E:E::1, subnet is E:E:E:E::/64
Joined group address(es):
FF02::1
FF02::2
FF02::5
FF02::1:FF00:1
FF02::1:FF98:0
MTU is 1400 bytes
ICMP error messages limited to one every 100 milliseconds
ICMP redirects are enabled
ND DAD is enabled, number of DAD attempts: 1
ND reachable time is 30000 milliseconds
Hosts use stateless autoconfig for addresses.
Based on the output provided in Examples 12-18 and 12-19, determine why router BB1 is
failing to form an OSPF adjacency with router BB2, via router BB1’s Serial 1/0.1 subinterface.
On a separate sheet of paper, write out your proposed solution to this issue.
Issue #3: Suggested Solution
The debug output seen in Example 12-18 indicates that router BB1’s neighbor (that is,
10.4.4.4) reachable over subinterface Serial 1/0.1 has a larger MTU than router BB1’s Serial
1/0.1 subinterface. The output in Example 12-19 indicates that router BB1’s Serial 1/0.1
subinterface has an MTU of 1400 bytes. This is less than the default value of 1500 bytes.
Example 12-20 shows how this MTU value was reset to its default value.
Example 12-20 Correcting the MTU on Router BB1’s Serial 1/0.1 Subinterface
BB1# conf term
Enter configuration commands, one per line. End with CNTL/Z.
BB1(config)# int s1/0.1
BB1(config-subif)# ipv6 mtu 1500
*Mar 1 00:20:00.019: %OSPFv3-5-ADJCHG: Process 1, Nbr 10.4.4.4 on Serial1/0.1
from LOADING to FULL, Loading Done
BB1(config-subif)# end
www.CareerCert.info
www.CareerCert.info
www - CareerCert - info
398 CCNP TSHOOT 642-832 Official Certification Guide
Notice, in Example 12-20, that an adjacency with router BB2 (that is, 10.4.4.4) was formed
over router BB1’s Serial 1/0.1 subinterface after setting the subinterface’s MTU size to the
default of 1500 bytes. Examples 12-21 and 12-22 further confirm that routers BB1 and
BB2 have formed all appropriate adjacencies with their OSPF neighbors.
Example 12-21 Router BB1’s OSPF Adjacencies
BB1# show ipv6 ospf neighbor
Neighbor ID Pri State Dead Time Interface ID Interface
10.2.2.2 1 FULL/ 00:00:37 13 Serial1/0.2
10.4.4.4 1 FULL/ 00:00:30 13 Serial1/0.1
10.4.4.4 1 FULL/DR 00:00:31 4 FastEthernet0/0
Example 12-22 Router BB2’s OSPF Adjacencies
BB2# show ipv6 ospf neighbor
Neighbor ID Pri State Dead Time Interface ID Interface
10.2.2.2 1 FULL/ 00:00:37 14 Serial1/0.2
10.3.3.3 1 FULL/ 00:00:37 13 Serial1/0.1
10.3.3.3 1 FULL/BDR 00:00:31 4 FastEthernet0/0
To confirm that full reachability has been restored in the network, a series of ping commands
were issued from router BB2, with one ping to each router in the topology. As seen
in Example 12-23, all of the pings were successful.
Example 12-23 Confirming Reachability to All Routers
BB2# ping a:a:a:a::11
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to A:A:A:A::11, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 88/124/164 ms
BB2# ping b:b:b:b::22
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to B:B:B:B::22, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 44/83/164 ms
BB2# ping f:f:f:f::1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to F:F:F:F::1, timeout is 2 seconds:
!!!!!
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