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OSPF の練習
本エントリについて
Dynagen、Dynamips を使って、OSPF を練習します。
Dynagen、Dynamips の利用環境はすでに整っているものとします。
基本設定
https://zenn.dev/mnod/articles/c273d13817e8a6 の基本設定と同じ構成
OSPF の有効化
area0 area0
[r1] area0 [r2]
OSPFの有効化するには、下記の方法があります。
-
networkコマンド使用 - インタフェースコンフィギュレーションモードで、
ip ospfコマンドを使用
r1 で有効化
ここでは network コマンドで有効化してみます。
r1(config)#router ospf 1
r1(config-router)#passive-interface fa0/0
r1(config-router)#network 172.16.0.253 0.0.0.255 area 0
r1(config-router)#network 10.2.0.0 0.0.0.255 area 0
状態を確認します。
r1#show ip protocols
Routing Protocol is "ospf 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 172.16.1.254
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.2.0.0 0.0.0.255 area 0
172.16.0.0 0.0.0.255 area 0
Reference bandwidth unit is 100 mbps
Passive Interface(s):
FastEthernet0/0
Routing Information Sources:
Gateway Distance Last Update
Distance: (default is 110)
r1#show ip ospf
Routing Process "ospf 1" with ID 172.16.1.254
Start time: 00:03:20.040, Time elapsed: 00:02:41.868
Supports only single TOS(TOS0) routes
Supports opaque LSA
Supports Link-local Signaling (LLS)
Supports area transit capability
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Incremental-SPF disabled
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
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 opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Number of areas transit capable is 0
External flood list length 0
IETF NSF helper support enabled
Cisco NSF helper support enabled
Area BACKBONE(0) (Inactive)
Number of interfaces in this area is 2
Area has no authentication
SPF algorithm last executed 00:00:43.688 ago
SPF algorithm executed 2 times
Area ranges are
Number of LSA 1. Checksum Sum 0x00E0B4
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
r1#show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet Address 10.2.0.254/24, Area 0
Process ID 1, Router ID 172.16.1.254, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.1.254, Interface address 10.2.0.254
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
No Hellos (Passive interface)
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
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)
Serial1/0 is up, line protocol is up
Internet Address 172.16.0.253/24, Area 0
Process ID 1, Router ID 172.16.1.254, 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
oob-resync timeout 40
Hello due in 00:00:07
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
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)
ネイバーテーブル、トポロジーテーブルを確認します。
他のルータではOSPFを起動していないので、ネイバーテーブルは空です。
トポロジーテーブル(LSDB、リンクステートデータベース)で Router Link States で表されるのは、LSA タイプ1(ルータLSA) です。
全てのOSPFルータで生成され、ルータID、リンク数、リンクの種類、コスト値を含みます。エリア内にフラッディングされます。
r1#show ip ospf neigh
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 164 0x80000002 0x00E0B4 2
r2 で有効化
ここでは ip ospf コマンドで有効化してみます。
r2(config)#router ospf 1
r2(config-router)#passive-interface f0/0
r2(config-router)#int f0/0
r2(config-if)#ip ospf 1 area 0
r2(config-if)#int s1/1
r2(config-if)#ip ospf 1 area 0
状態を確認します。
r2#show ip protocols
Routing Protocol is "ospf 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 172.16.2.253
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
Routing on Interfaces Configured Explicitly (Area 0):
FastEthernet0/0
Serial1/1
Reference bandwidth unit is 100 mbps
Passive Interface(s):
FastEthernet0/0
Routing Information Sources:
Gateway Distance Last Update
172.16.1.254 110 00:01:05
Distance: (default is 110)
r2#show ip ospf
Routing Process "ospf 1" with ID 172.16.2.253
Start time: 00:10:44.548, Time elapsed: 00:02:47.008
Supports only single TOS(TOS0) routes
Supports opaque LSA
Supports Link-local Signaling (LLS)
Supports area transit capability
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Incremental-SPF disabled
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
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 opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Number of areas transit capable is 0
External flood list length 0
IETF NSF helper support enabled
Cisco NSF helper support enabled
Area BACKBONE(0)
Number of interfaces in this area is 2
Area has no authentication
SPF algorithm last executed 00:01:12.656 ago
SPF algorithm executed 3 times
Area ranges are
Number of LSA 2. Checksum Sum 0x012278
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
r2#show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet Address 10.2.1.254/24, Area 0
Process ID 1, Router ID 172.16.2.253, Network Type BROADCAST, Cost: 10
Enabled by interface config, including secondary ip addresses
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.2.253, Interface address 10.2.1.254
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
No Hellos (Passive interface)
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
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)
Serial1/1 is up, line protocol is up
Internet Address 172.16.0.254/24, Area 0
Process ID 1, Router ID 172.16.2.253, Network Type POINT_TO_POINT, Cost: 64
Enabled by interface config, including secondary ip addresses
Transmit Delay is 1 sec, State POINT_TO_POINT
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
Hello due in 00:00:01
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.1.254
Suppress hello for 0 neighbor(s)
ネイバーテーブル、トポロジーテーブル、ルーティングテーブルを確認します。
r1 をネイバーと認識しました。
r2#show ip ospf neigh
Neighbor ID Pri State Dead Time Address Interface
172.16.1.254 0 FULL/ - 00:00:37 172.16.0.253 Serial1/1
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 171 0x80000003 0x00804E 3
172.16.2.253 172.16.2.253 138 0x80000003 0x00A22A 3
r2#show ip route ospf
10.0.0.0/24 is subnetted, 2 subnets
O 10.2.0.0 [110/74] via 172.16.0.253, 00:02:21, Serial1/1
r1でもネイバーテーブル、トポロジーテーブル、ルーティングテーブルを確認します。
こちらも r2 をネイバーと認識しました。
r1#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.2.253 0 FULL/ - 00:00:37 172.16.0.254 Serial1/0
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 207 0x80000003 0x00804E 3
172.16.2.253 172.16.2.253 177 0x80000003 0x00A22A 3
r1#show ip route ospf
10.0.0.0/24 is subnetted, 2 subnets
O 10.2.1.0 [110/74] via 172.16.0.254, 00:03:30, Serial1/0
認証
OSPFの認証設定は以下の方法があります。
- インタフェースごとに有効化
- エリアごとに裕逢花
インタフェースで有効化
r1(config)#int s1/0
r1(config-if)#ip ospf message-digest-key 1 md5 cisco
r1(config-if)#ip ospf authentication message-digest
状態を確認します。
r1#show ip ospf interface s1/0
Serial1/0 is up, line protocol is up
Internet Address 172.16.0.253/24, Area 0
Process ID 1, Router ID 172.16.1.254, 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
oob-resync timeout 40
Hello due in 00:00:08
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
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)
Message digest authentication enabled
Youngest key id is 1
ネイバーテーブル、トポロジーテーブル、ルーティングテーブルを確認します。
認証不一致のため、ネイバー関係が解消しました。
r1#show ip ospf neigh
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 65 0x80000004 0x00DCB6 2
172.16.2.253 172.16.2.253 578 0x80000003 0x00A22A 3
r1#show ip route ospf
r2でもネイバーテーブル、トポロジーテーブル、ルーティングテーブルを確認しておきます。
r2#show ip ospf neigh
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 670 0x80000003 0x00804E 3
172.16.2.253 172.16.2.253 124 0x80000004 0x00E3AE 2
r2#show ip route ospf
エリアで有効化
r2(config)#interface s1/1
r2(config-if)#ip ospf message-digest-key 1 md5 cisco
r2(config-if)#router ospf 1
r2(config-router)#area 0 authentication message-digest
状態を確認します。
r2#show ip ospf
Routing Process "ospf 1" with ID 172.16.2.253
Start time: 00:10:44.548, Time elapsed: 00:14:45.784
Supports only single TOS(TOS0) routes
Supports opaque LSA
Supports Link-local Signaling (LLS)
Supports area transit capability
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Incremental-SPF disabled
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
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 opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Number of areas transit capable is 0
External flood list length 0
IETF NSF helper support enabled
Cisco NSF helper support enabled
Area BACKBONE(0)
Number of interfaces in this area is 2
Area has message digest authentication
SPF algorithm last executed 00:00:52.424 ago
SPF algorithm executed 5 times
Area ranges are
Number of LSA 2. Checksum Sum 0x011A7C
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
r2#show ip ospf int s1/1
Serial1/1 is up, line protocol is up
Internet Address 172.16.0.254/24, Area 0
Process ID 1, Router ID 172.16.2.253, Network Type POINT_TO_POINT, Cost: 64
Enabled by interface config, including secondary ip addresses
Transmit Delay is 1 sec, State POINT_TO_POINT
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
Hello due in 00:00:08
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.1.254
Suppress hello for 0 neighbor(s)
Message digest authentication enabled
Youngest key id is 1
ネイバーテーブル、トポロジーテーブル、ルーティングテーブルを確認します。
ネイバー関係が回復し、ルーティングテーブルに経路が乗りました。
r2#show ip ospf neigh
Neighbor ID Pri State Dead Time Address Interface
172.16.1.254 0 FULL/ - 00:00:33 172.16.0.253 Serial1/1
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 192 0x80000005 0x007C50 3
172.16.2.253 172.16.2.253 191 0x80000005 0x009E2C 3
r2#show ip route ospf
10.0.0.0/24 is subnetted, 2 subnets
O 10.2.0.0 [110/74] via 172.16.0.253, 00:03:14, Serial1/1
r1でもネイバーテーブル、トポロジーテーブル、ルーティングテーブルを確認します。
r1#show ip ospf neigh
Neighbor ID Pri State Dead Time Address Interface
172.16.2.253 0 FULL/ - 00:00:34 172.16.0.254 Serial1/0
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 225 0x80000005 0x007C50 3
172.16.2.253 172.16.2.253 226 0x80000005 0x009E2C 3
r1#show ip route ospf
10.0.0.0/24 is subnetted, 2 subnets
O 10.2.1.0 [110/74] via 172.16.0.254, 00:03:46, Serial1/0
エリアごとの認証だとこの後の練習で面倒なので、r2もインタフェースごとの認証にしておきます。
r2(config-if)#router ospf 1
r2(config-router)#no area 0 authentication message-digest
r2(config-router)#int s1/1
r2(config-if)#ip ospf authentication message-digest
マルチアエリア
エリア0だけの構成でしたが、エリア1を追加してみます。
area0 area0 area1
[r1] area0 [r2] area1 [r4]
r2 で area 1 の追加
r2(config)#router ospf 1
r2(config-router)#network 172.16.2.0 0.0.0.255 area 1
状態を確認します。
r2#show ip protocols
Routing Protocol is "ospf 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 172.16.2.253
It is an area border router
Number of areas in this router is 2. 2 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
172.16.2.0 0.0.0.255 area 1
Routing on Interfaces Configured Explicitly (Area 0):
FastEthernet0/0
Serial1/1
Reference bandwidth unit is 100 mbps
Passive Interface(s):
FastEthernet0/0
Routing Information Sources:
Gateway Distance Last Update
172.16.1.254 110 00:00:09
Distance: (default is 110)
r2#show ip ospf
Routing Process "ospf 1" with ID 172.16.2.253
Start time: 00:10:44.548, Time elapsed: 00:34:33.860
Supports only single TOS(TOS0) routes
Supports opaque LSA
Supports Link-local Signaling (LLS)
Supports area transit capability
It is an area border router
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Incremental-SPF disabled
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
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 opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 2. 2 normal 0 stub 0 nssa
Number of areas transit capable is 0
External flood list length 0
IETF NSF helper support enabled
Cisco NSF helper support enabled
Area BACKBONE(0)
Number of interfaces in this area is 2
Area has no authentication
SPF algorithm last executed 00:00:52.440 ago
SPF algorithm executed 7 times
Area ranges are
Number of LSA 3. Checksum Sum 0x01F71E
Number of opaque link LSA 0. Checksum Sum 0x000000
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
Area has no authentication
SPF algorithm last executed 00:00:52.448 ago
SPF algorithm executed 2 times
Area ranges are
Number of LSA 4. Checksum Sum 0x028648
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
r2#show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet Address 10.2.1.254/24, Area 0
Process ID 1, Router ID 172.16.2.253, Network Type BROADCAST, Cost: 10
Enabled by interface config, including secondary ip addresses
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 172.16.2.253, Interface address 10.2.1.254
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
No Hellos (Passive interface)
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
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)
Serial1/1 is up, line protocol is up
Internet Address 172.16.0.254/24, Area 0
Process ID 1, Router ID 172.16.2.253, Network Type POINT_TO_POINT, Cost: 64
Enabled by interface config, including secondary ip addresses
Transmit Delay is 1 sec, State POINT_TO_POINT
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
Hello due in 00:00:05
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.1.254
Suppress hello for 0 neighbor(s)
Message digest authentication enabled
Youngest key id is 1
Serial1/0 is up, line protocol is up
Internet Address 172.16.2.253/24, Area 1
Process ID 1, Router ID 172.16.2.253, 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
oob-resync timeout 40
Hello due in 00:00:06
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 1/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
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)
トポロジーテーブルを確認します。r2 はエリア0とエリア1をまたがる ABR なので、それぞれのエリアの LSA をもっています。
Summary Net Link States は LSA タイプ3(ネットワーク集約LSA) を表します。ABR が生成し、各エリアごとの経路情報、コスト値を含みます。各エリア内にフラッディングします。
(経路の集約は自分で設定する必要があります。)
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1300 0x80000005 0x007C50 3
172.16.2.253 172.16.2.253 110 0x80000006 0x009F29 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.2.0 172.16.2.253 106 0x80000001 0x00DBA5
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 110 0x80000001 0x009F1A 1
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
10.2.0.0 172.16.2.253 111 0x80000001 0x0041E8
10.2.1.0 172.16.2.253 111 0x80000001 0x00B3B5
172.16.0.0 172.16.2.253 114 0x80000001 0x00F191
r1でトポロジーテーブル、ルーティングテーブルを確認します。
r1が属しているのは Area 0 のみなので、Area 0 の LSA のみを持っています。
ルーティングテーブルにおいて、他のエリアの経路には O IA のコードがつきます。ここでは、エリア1 の経路に O IA のコードがついています。
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1368 0x80000005 0x007C50 3
172.16.2.253 172.16.2.253 180 0x80000006 0x009F29 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.2.0 172.16.2.253 176 0x80000001 0x00DBA5
r1#show ip route ospf
172.16.0.0/24 is subnetted, 3 subnets
O IA 172.16.2.0 [110/128] via 172.16.0.254, 00:03:25, Serial1/0
10.0.0.0/24 is subnetted, 2 subnets
O 10.2.1.0 [110/74] via 172.16.0.254, 00:23:14, Serial1/0
r4 で有効化
r4(config)#router ospf 1
r4(config-router)#network 172.16.2.0 0.0.0.255 area 1
r4(config-router)#network 10.2.3.0 0.0.0.255 area 1
r4(config-router)#passive-interface f0/0
状態を確認します。
r4#show ip protocols
Routing Protocol is "ospf 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 192.168.3.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.2.3.0 0.0.0.255 area 1
172.16.2.0 0.0.0.255 area 1
Reference bandwidth unit is 100 mbps
Passive Interface(s):
FastEthernet0/0
Routing Information Sources:
Gateway Distance Last Update
172.16.2.253 110 00:00:19
Distance: (default is 110)
r4#show ip ospf
Routing Process "ospf 1" with ID 192.168.3.1
Start time: 00:47:30.748, Time elapsed: 00:02:16.436
Supports only single TOS(TOS0) routes
Supports opaque LSA
Supports Link-local Signaling (LLS)
Supports area transit capability
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Incremental-SPF disabled
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
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 opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Number of areas transit capable is 0
External flood list length 0
IETF NSF helper support enabled
Cisco NSF helper support enabled
Area 1
Number of interfaces in this area is 2
Area has no authentication
SPF algorithm last executed 00:00:30.740 ago
SPF algorithm executed 3 times
Area ranges are
Number of LSA 5. Checksum Sum 0x026B50
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
r4#show ip ospf interface
FastEthernet0/0 is up, line protocol is up
Internet Address 10.2.3.254/24, Area 1
Process ID 1, Router ID 192.168.3.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 192.168.3.1, Interface address 10.2.3.254
No backup designated router on this network
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
No Hellos (Passive interface)
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
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)
Serial1/1 is up, line protocol is up
Internet Address 172.16.2.254/24, Area 1
Process ID 1, Router ID 192.168.3.1, 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
oob-resync timeout 40
Hello due in 00:00:07
Supports Link-local Signaling (LLS)
Cisco NSF helper support enabled
IETF NSF helper support enabled
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 172.16.2.253
Suppress hello for 0 neighbor(s)
ネイバーテーブル、トポロジーテーブル、ルーティングテーブルを確認します。
属しているのは Area 1 のみなので、Area 1 の LSA のみを持っています。
ルーティングテーブルで O IA のコードがついているのは、エリア0 の経路です。
r4#show ip ospf neigh
Neighbor ID Pri State Dead Time Address Interface
172.16.2.253 0 FULL/ - 00:00:31 172.16.2.253 Serial1/1
r4#show ip ospf database
OSPF Router with ID (192.168.3.1) (Process ID 1)
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 154 0x80000002 0x0041FE 2
192.168.3.1 192.168.3.1 131 0x80000002 0x004224 3
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
10.2.0.0 172.16.2.253 451 0x80000001 0x0041E8
10.2.1.0 172.16.2.253 451 0x80000001 0x00B3B5
172.16.0.0 172.16.2.253 451 0x80000001 0x00F191
r4#show ip route ospf
172.16.0.0/24 is subnetted, 3 subnets
O IA 172.16.0.0 [110/128] via 172.16.2.253, 00:01:30, Serial1/1
10.0.0.0/24 is subnetted, 3 subnets
O IA 10.2.0.0 [110/138] via 172.16.2.253, 00:01:30, Serial1/1
O IA 10.2.1.0 [110/74] via 172.16.2.253, 00:01:30, Serial1/1
r2でもネイバーテーブル、トポロジーテーブル、ルーティングテーブルを確認します。
ABR では属している両方のエリアのタイプ1 LSAを持っているので、ルーティングテーブルでは O IA のコードは現れません。
r2#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.1.254 0 FULL/ - 00:00:31 172.16.0.253 Serial1/1
192.168.3.1 0 FULL/ - 00:00:33 172.16.2.254 Serial1/0
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1678 0x80000005 0x007C50 3
172.16.2.253 172.16.2.253 488 0x80000006 0x009F29 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.2.3.0 172.16.2.253 163 0x80000001 0x002007
172.16.2.0 172.16.2.253 484 0x80000001 0x00DBA5
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 190 0x80000002 0x0041FE 2
192.168.3.1 192.168.3.1 169 0x80000002 0x004224 3
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
10.2.0.0 172.16.2.253 489 0x80000001 0x0041E8
10.2.1.0 172.16.2.253 491 0x80000001 0x00B3B5
172.16.0.0 172.16.2.253 491 0x80000001 0x00F191
r2#show ip route ospf
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.0.0 [110/74] via 172.16.0.253, 00:08:34, Serial1/1
O 10.2.3.0 [110/74] via 172.16.2.254, 00:03:08, Serial1/0
r1でトポロジーテーブル、ルーティングテーブルを確認します。
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1718 0x80000005 0x007C50 3
172.16.2.253 172.16.2.253 531 0x80000006 0x009F29 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.2.3.0 172.16.2.253 206 0x80000001 0x002007
172.16.2.0 172.16.2.253 527 0x80000001 0x00DBA5
r1#show ip route ospf
172.16.0.0/24 is subnetted, 3 subnets
O IA 172.16.2.0 [110/128] via 172.16.0.254, 00:08:53, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.1.0 [110/74] via 172.16.0.254, 00:28:42, Serial1/0
O IA 10.2.3.0 [110/138] via 172.16.0.254, 00:03:33, Serial1/0
abr での経路集約
経路集約によって、LSA の数を減らすことができます。計算の負荷が減り、ルーティングテーブルも小さくなります。
area0 area0 area1
[r1] area0 [r2] area1 [r4]
subinterface
192.168.0.0/24
192.168.1.0/24
192.168.2.0/24
192.168.3.0/24
経路集約を試すために r4 で下記のようにアドレスを追加します。
r4(config)#int f0/1.0
r4(config-if)#ip addr 192.168.0.1 255.255.255.0
r4(config-if)#no shut
r4(config-if)#int f0/1.1
r4(config-subif)#encapsulation dot1Q 1
r4(config-subif)#ip addr 192.168.1.1 255.255.255.0
r4(config-subif)#no shut
r4(config-subif)#int f0/1.2
r4(config-subif)#encapsulation dot1Q 2
r4(config-subif)#ip addr 192.168.2.1 255.255.255.0
r4(config-subif)#no shut
r4(config-subif)#int f0/1.3
r4(config-subif)#encapsulation dot1Q 3
r4(config-subif)#ip addr 192.168.3.1 255.255.255.0
r4(config-subif)#no shut
r4#show ip int bri
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 10.2.3.254 YES NVRAM up up
FastEthernet0/1 192.168.0.1 YES manual up up
FastEthernet0/1.1 192.168.1.1 YES manual up up
FastEthernet0/1.2 192.168.2.1 YES manual up up
FastEthernet0/1.3 192.168.3.1 YES manual up up
Serial1/0 172.16.3.253 YES NVRAM up up
Serial1/1 172.16.2.254 YES NVRAM up up
Serial1/2 unassigned YES NVRAM administratively down down
Serial1/3 unassigned YES NVRAM administratively down down
追加したインタフェースで ospf を有効にします。
r4(config)#router ospf 1
r4(config-router)#network 192.168.0.0 0.0.3.255 area 1
状態を確認します。
ルータIDが、設定したIPアドレスのうちの最大のものである 192.168.3.1 に変化しています。
r4#show ip protocols
Routing Protocol is "ospf 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 192.168.3.1
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.2.3.0 0.0.0.255 area 1
172.16.2.0 0.0.0.255 area 1
192.168.0.0 0.0.3.255 area 1
Reference bandwidth unit is 100 mbps
Passive Interface(s):
FastEthernet0/0
Routing Information Sources:
Gateway Distance Last Update
172.16.2.253 110 00:05:05
Distance: (default is 110)
トポロジーテーブルを確認します。
r4#show ip ospf database
OSPF Router with ID (192.168.3.1) (Process ID 1)
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 454 0x80000002 0x0041FE 2
192.168.3.1 192.168.3.1 105 0x80000003 0x00FA56 7
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
10.2.0.0 172.16.2.253 752 0x80000001 0x0041E8
10.2.1.0 172.16.2.253 752 0x80000001 0x00B3B5
172.16.0.0 172.16.2.253 752 0x80000001 0x00F191
r2でもトポロジーテーブル、ルーティングテーブルを確認します。
追加した経路に対して、現段階では 192.168.0.0/24 から 192.168.3.0/24 の4つのタイプ3LSAが見られます。
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 9 0x80000006 0x007A51 3
172.16.2.253 172.16.2.253 795 0x80000006 0x009F29 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.2.3.0 172.16.2.253 470 0x80000001 0x002007
172.16.2.0 172.16.2.253 790 0x80000001 0x00DBA5
192.168.0.0 172.16.2.253 144 0x80000001 0x002AA2
192.168.1.0 172.16.2.253 144 0x80000001 0x001FAC
192.168.2.0 172.16.2.253 144 0x80000001 0x0014B6
192.168.3.0 172.16.2.253 144 0x80000001 0x0009C0
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 497 0x80000002 0x0041FE 2
192.168.3.1 192.168.3.1 150 0x80000003 0x00FA56 7
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
10.2.0.0 172.16.2.253 798 0x80000001 0x0041E8
10.2.1.0 172.16.2.253 798 0x80000001 0x00B3B5
172.16.0.0 172.16.2.253 798 0x80000001 0x00F191
r2#show ip route ospf
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.0.0 [110/74] via 172.16.0.253, 00:13:28, Serial1/1
O 10.2.3.0 [110/74] via 172.16.2.254, 00:08:02, Serial1/0
O 192.168.0.0/24 [110/74] via 172.16.2.254, 00:02:37, Serial1/0
O 192.168.1.0/24 [110/74] via 172.16.2.254, 00:02:37, Serial1/0
O 192.168.2.0/24 [110/74] via 172.16.2.254, 00:02:37, Serial1/0
O 192.168.3.0/24 [110/74] via 172.16.2.254, 00:02:37, Serial1/0
r1でもトポロジーテーブル、ルーティングテーブルを確認します。
r4 で追加したアドレスが O IA のコードで、 192.168.0.0/24 から 192.168.3.0/24 の4つのルートが乗っています。
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 34 0x80000006 0x007A51 3
172.16.2.253 172.16.2.253 822 0x80000006 0x009F29 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.2.3.0 172.16.2.253 497 0x80000001 0x002007
172.16.2.0 172.16.2.253 818 0x80000001 0x00DBA5
192.168.0.0 172.16.2.253 171 0x80000001 0x002AA2
192.168.1.0 172.16.2.253 171 0x80000001 0x001FAC
192.168.2.0 172.16.2.253 171 0x80000001 0x0014B6
192.168.3.0 172.16.2.253 171 0x80000001 0x0009C0
r1#show ip route ospf
172.16.0.0/24 is subnetted, 3 subnets
O IA 172.16.2.0 [110/128] via 172.16.0.254, 00:13:40, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.1.0 [110/74] via 172.16.0.254, 00:33:29, Serial1/0
O IA 10.2.3.0 [110/138] via 172.16.0.254, 00:08:20, Serial1/0
O IA 192.168.0.0/24 [110/138] via 172.16.0.254, 00:02:54, Serial1/0
O IA 192.168.1.0/24 [110/138] via 172.16.0.254, 00:02:54, Serial1/0
O IA 192.168.2.0/24 [110/138] via 172.16.0.254, 00:02:54, Serial1/0
O IA 192.168.3.0/24 [110/138] via 172.16.0.254, 00:02:54, Serial1/0
ABR である r2 で経路集約を設定します。
r2(config)#router ospf 1
r2(config-router)#area 1 range 192.168.0.0 255.255.252.0
トポロジーテーブル、ルーティングテーブルを確認します。
r4で追加したアドレスについてのタイプ3 SLA が 192.168.0.0 の一つだけになりました。
ルーティングテーブルに Null0 デバイスの経路ができました。
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 138 0x80000006 0x007A51 3
172.16.2.253 172.16.2.253 924 0x80000006 0x009F29 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.2.3.0 172.16.2.253 599 0x80000001 0x002007
172.16.2.0 172.16.2.253 920 0x80000001 0x00DBA5
192.168.0.0 172.16.2.253 26 0x80000002 0x0019B5
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 626 0x80000002 0x0041FE 2
192.168.3.1 192.168.3.1 280 0x80000003 0x00FA56 7
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
10.2.0.0 172.16.2.253 925 0x80000001 0x0041E8
10.2.1.0 172.16.2.253 927 0x80000001 0x00B3B5
172.16.0.0 172.16.2.253 927 0x80000001 0x00F191
r2#show ip route ospf
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.0.0 [110/74] via 172.16.0.253, 00:00:43, Serial1/1
O 10.2.3.0 [110/74] via 172.16.2.254, 00:00:43, Serial1/0
O 192.168.0.0/24 [110/74] via 172.16.2.254, 00:00:43, Serial1/0
O 192.168.1.0/24 [110/74] via 172.16.2.254, 00:00:43, Serial1/0
O 192.168.2.0/24 [110/74] via 172.16.2.254, 00:00:43, Serial1/0
O 192.168.3.0/24 [110/74] via 172.16.2.254, 00:00:43, Serial1/0
O 192.168.0.0/22 is a summary, 00:00:43, Null0
r1でもトポロジーテーブル、ルーティングテーブルを確認します。
r4で追加したアドレスについてのタイプ3 SLA が 192.168.0.0 の一つだけになりました。
ルーティングテーブルに乗る経路が 192.168.0.0/22 の一つだけになりました。
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 198 0x80000006 0x007A51 3
172.16.2.253 172.16.2.253 986 0x80000006 0x009F29 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.2.3.0 172.16.2.253 661 0x80000001 0x002007
172.16.2.0 172.16.2.253 981 0x80000001 0x00DBA5
192.168.0.0 172.16.2.253 88 0x80000002 0x0019B5
r1#show ip route ospf
172.16.0.0/24 is subnetted, 3 subnets
O IA 172.16.2.0 [110/128] via 172.16.0.254, 00:16:28, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.1.0 [110/74] via 172.16.0.254, 00:36:17, Serial1/0
O IA 10.2.3.0 [110/138] via 172.16.0.254, 00:11:08, Serial1/0
O IA 192.168.0.0/22 [110/138] via 172.16.0.254, 00:01:35, Serial1/0
再配送
area0 area0
[r1] area0 [r2] eigrp1 [r4]
静的ルート、外部ルートを再配送することができます。
ここでは EIGRP の AS1で学習したルートの再配送を練習します。
EIGRP を有効化
r2(config)#router ospf 1
r2(config-router)#no network 172.16.2.0 0.0.0.255 area 1
r2(config)#router eigrp 1
r2(config-router)#no auto-summary
r2(config-router)#network 172.16.2.0 0.0.0.255
状態を確認します。
r2#show ip protocols
Routing Protocol is "ospf 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 172.16.2.253
Number of areas in this router is 2. 2 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
Routing on Interfaces Configured Explicitly (Area 0):
FastEthernet0/0
Serial1/1
Reference bandwidth unit is 100 mbps
Passive Interface(s):
FastEthernet0/0
Routing Information Sources:
Gateway Distance Last Update
172.16.2.253 110 00:12:00
172.16.1.254 110 00:12:00
192.168.3.1 110 00:12:00
Distance: (default is 110)
Routing Protocol is "eigrp 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 1
EIGRP NSF-aware route hold timer is 240s
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
172.16.2.0/24
Routing Information Sources:
Gateway Distance Last Update
Distance: internal 90 external 170
r4 でEIGPR を有効化します。
r4(config)#no router ospf 1
r4(config)#router eigrp 1
r4(config-router)#passive-interface f0/0
r4(config-router)#no auto-summary
r4(config-router)#network 172.16.2.0 0.0.0.255
r4(config-router)#network 10.2.3.0 0.0.0.255
状態を確認します。
r4#show ip protocols
Routing Protocol is "eigrp 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
EIGRP maximum metric variance 1
Redistributing: eigrp 1
EIGRP NSF-aware route hold timer is 240s
Automatic network summarization is not in effect
Maximum path: 4
Routing for Networks:
10.2.3.0/24
172.16.2.0/24
Passive Interface(s):
FastEthernet0/0
Routing Information Sources:
Gateway Distance Last Update
(this router) 90 00:01:15
172.16.2.253 90 00:01:04
Distance: internal 90 external 170
r4#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 2 subnets
C 172.16.2.0 is directly connected, Serial1/1
C 172.16.3.0 is directly connected, Serial1/0
10.0.0.0/24 is subnetted, 1 subnets
C 10.2.3.0 is directly connected, FastEthernet0/0
C 192.168.0.0/24 is directly connected, FastEthernet0/1
C 192.168.1.0/24 is directly connected, FastEthernet0/1.1
C 192.168.2.0/24 is directly connected, FastEthernet0/1.2
C 192.168.3.0/24 is directly connected, FastEthernet0/1.3
r2 でルーティングテーブルを確認します。
r2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 2 subnets
C 172.16.0.0 is directly connected, Serial1/1
C 172.16.2.0 is directly connected, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.0.0 [110/74] via 172.16.0.253, 01:37:25, Serial1/1
C 10.2.1.0 is directly connected, FastEthernet0/0
D 10.2.3.0 [90/2195456] via 172.16.2.254, 01:23:07, Serial1/0
再配送設定
r2で 再配送の設定をします。
EIGRP 側に OSPF のルートを再配送してみます。
r2(config)#router eigrp 1
r2(config-router)#redistribute ospf 1
r2(config-router)#default-metric 1533 2000 255 1 1500
r4のルーティングテーブルを確認します。
r4#show ip eigrp topology
IP-EIGRP Topology Table for AS(1)/ID(192.168.3.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 10.2.0.0/24, 1 successors, FD is 2693888
via 172.16.2.253 (2693888/2181888), Serial1/1
P 10.2.1.0/24, 1 successors, FD is 2693888
via 172.16.2.253 (2693888/2181888), Serial1/1
P 10.2.3.0/24, 1 successors, FD is 281600
via Connected, FastEthernet0/0
P 172.16.0.0/24, 1 successors, FD is 2693888
via 172.16.2.253 (2693888/2181888), Serial1/1
P 172.16.2.0/24, 1 successors, FD is 2169856
via Connected, Serial1/1
r4#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets
D EX 172.16.0.0 [170/2693888] via 172.16.2.253, 00:00:18, Serial1/1
C 172.16.2.0 is directly connected, Serial1/1
C 172.16.3.0 is directly connected, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
D EX 10.2.0.0 [170/2693888] via 172.16.2.253, 00:00:18, Serial1/1
D EX 10.2.1.0 [170/2693888] via 172.16.2.253, 00:00:18, Serial1/1
C 10.2.3.0 is directly connected, FastEthernet0/0
C 192.168.0.0/24 is directly connected, FastEthernet0/1
C 192.168.1.0/24 is directly connected, FastEthernet0/1.1
C 192.168.2.0/24 is directly connected, FastEthernet0/1.2
C 192.168.3.0/24 is directly connected, FastEthernet0/1.3
今度は OSPF 側に EIGRP のルートを再配送してみます。
r2(config)#router ospf 1
r2(config-router)#redistribute eigrp 1 metric-type 1 subnets
トポロジーテーブルの Type-5 AS External Link States は LSA タイプ5(AS外部LSA) を表します。
ASBR で生成され、外部ルートから再配布した経路情報、コスト、ネクストホップを含みます。スタブエリア、NSSAエリアを除くOSPFのAS全体にフラッディングされます。
r2# show ip ospf datab
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1170 0x80000007 0x007852 3
172.16.2.253 172.16.2.253 16 0x80000009 0x005A6A 3
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 16 0x80000004 0x008143 0
172.16.3.253 172.16.3.253 618 0x80000003 0x00D0DF 7
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.2.3.0 172.16.2.253 15 0x80000001 0x001441 0
172.16.2.0 172.16.2.253 15 0x80000001 0x003471 0
r1でルーティングテーブルを確認します。
r1# show ip ospf datab
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1274 0x80000007 0x007852 3
172.16.2.253 172.16.2.253 121 0x80000009 0x005A6A 3
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.2.3.0 172.16.2.253 121 0x80000001 0x001441 0
172.16.2.0 172.16.2.253 121 0x80000001 0x003471 0
r1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets
C 172.16.0.0 is directly connected, Serial1/0
C 172.16.1.0 is directly connected, Serial1/1
O E1 172.16.2.0 [110/84] via 172.16.0.254, 00:00:46, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
C 10.2.0.0 is directly connected, FastEthernet0/0
O 10.2.1.0 [110/74] via 172.16.0.254, 02:26:41, Serial1/0
O E1 10.2.3.0 [110/84] via 172.16.0.254, 00:00:46, Serial1/0
asbr での経路集約
area0 area0
[r1] area0 [r2] eigrp1 [r4]
subinterface
192.168.0.0/24
192.168.1.0/24
192.168.2.0/24
192.168.3.0/24
経路集約の練習のために追加したアドレスを EIGRP にアドバタイズします。
r4(config)#router eigrp 1
r4(config-router)#network 192.168.0.0 0.0.3.255
r2 でトポロジーテーブルとルーティングテーブルを確認します。
r4 で追加したアドレスは192.168.0.0/24 から 192.168.3.0/24 の4つのLSAでトポロジーテーブルに登録されています。
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1408 0x80000009 0x007454 3
172.16.2.253 172.16.2.253 658 0x8000000B 0x00982A 3
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 658 0x80000008 0x007947 0
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.2.3.0 172.16.2.253 636 0x80000001 0x001441 0
172.16.2.0 172.16.2.253 636 0x80000001 0x003471 0
192.168.0.0 172.16.2.253 108 0x80000001 0x001EDC 0
192.168.1.0 172.16.2.253 108 0x80000001 0x0013E6 0
192.168.2.0 172.16.2.253 108 0x80000001 0x0008F0 0
192.168.3.0 172.16.2.253 108 0x80000001 0x00FCFA 0
r2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 2 subnets
C 172.16.0.0 is directly connected, Serial1/1
C 172.16.2.0 is directly connected, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.0.0 [110/74] via 172.16.0.253, 02:00:37, Serial1/1
C 10.2.1.0 is directly connected, FastEthernet0/0
D 10.2.3.0 [90/2195456] via 172.16.2.254, 01:46:19, Serial1/0
D 192.168.0.0/24 [90/2195456] via 172.16.2.254, 00:00:35, Serial1/0
D 192.168.1.0/24 [90/2195456] via 172.16.2.254, 00:00:35, Serial1/0
D 192.168.2.0/24 [90/2195456] via 172.16.2.254, 00:00:37, Serial1/0
D 192.168.3.0/24 [90/2195456] via 172.16.2.254, 00:00:37, Serial1/0
r1 でもトポロジーテーブルとルーティングテーブルを確認します。
LSA タイプ5の経路は O E1 O E2 でルーティングテーブルに乗ります。
経路集約されていないので 192.168.0.0/24 から 192.168.3.0/24 の4つのLSA、経路が見られます。
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1393 0x80000009 0x007454 3
172.16.2.253 172.16.2.253 645 0x8000000B 0x00982A 3
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.2.3.0 172.16.2.253 623 0x80000001 0x001441 0
172.16.2.0 172.16.2.253 623 0x80000001 0x003471 0
192.168.0.0 172.16.2.253 95 0x80000001 0x001EDC 0
192.168.1.0 172.16.2.253 95 0x80000001 0x0013E6 0
192.168.2.0 172.16.2.253 95 0x80000001 0x0008F0 0
192.168.3.0 172.16.2.253 95 0x80000001 0x00FCFA 0
r1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets
C 172.16.0.0 is directly connected, Serial1/0
C 172.16.1.0 is directly connected, Serial1/1
O E1 172.16.2.0 [110/84] via 172.16.0.254, 00:11:01, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
C 10.2.0.0 is directly connected, FastEthernet0/0
O 10.2.1.0 [110/74] via 172.16.0.254, 02:36:56, Serial1/0
O E1 10.2.3.0 [110/84] via 172.16.0.254, 00:11:01, Serial1/0
O E1 192.168.0.0/24 [110/84] via 172.16.0.254, 00:02:13, Serial1/0
O E1 192.168.1.0/24 [110/84] via 172.16.0.254, 00:02:14, Serial1/0
O E1 192.168.2.0/24 [110/84] via 172.16.0.254, 00:02:14, Serial1/0
O E1 192.168.3.0/24 [110/84] via 172.16.0.254, 00:02:14, Serial1/0
asbr で経路集約
r2 で経路集約の設定をします。
r2(config)#router ospf 1
r2(config-router)#summary-address 192.168.0.0 255.255.252.0
トポロジーテーブルを確認します。 192.168.0.0 の一つに集約されました。
ルーティングテーブルに Null0 の集約ルートが乗りました。
r2#show ip ospf database
OSPF Router with ID (172.16.2.253) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1651 0x80000009 0x007454 3
172.16.2.253 172.16.2.253 901 0x8000000B 0x00982A 3
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.16.2.253 172.16.2.253 901 0x80000008 0x007947 0
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.2.3.0 172.16.2.253 879 0x80000001 0x001441 0
172.16.2.0 172.16.2.253 879 0x80000001 0x003471 0
192.168.0.0 172.16.2.253 50 0x80000002 0x000DEF 0
r2# show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 2 subnets
C 172.16.0.0 is directly connected, Serial1/1
C 172.16.2.0 is directly connected, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
O 10.2.0.0 [110/74] via 172.16.0.253, 00:34:25, Serial1/1
C 10.2.1.0 is directly connected, FastEthernet0/0
D 10.2.3.0 [90/2195456] via 172.16.2.254, 00:30:46, Serial1/0
D 192.168.0.0/24 [90/2195456] via 172.16.2.254, 00:20:37, Serial1/0
D 192.168.1.0/24 [90/2195456] via 172.16.2.254, 00:20:37, Serial1/0
D 192.168.2.0/24 [90/2195456] via 172.16.2.254, 00:20:38, Serial1/0
D 192.168.3.0/24 [90/2195456] via 172.16.2.254, 00:20:38, Serial1/0
O 192.168.0.0/22 is a summary, 00:18:19, Null0
r1 でトポロジーテーブルとルーティングテーブルを確認します。
r1#show ip ospf database
OSPF Router with ID (172.16.1.254) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
172.16.1.254 172.16.1.254 1741 0x80000009 0x007454 3
172.16.2.253 172.16.2.253 993 0x8000000B 0x00982A 3
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
10.2.3.0 172.16.2.253 971 0x80000001 0x001441 0
172.16.2.0 172.16.2.253 971 0x80000001 0x003471 0
192.168.0.0 172.16.2.253 142 0x80000002 0x000DEF 0
r1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets
C 172.16.0.0 is directly connected, Serial1/0
C 172.16.1.0 is directly connected, Serial1/1
O E1 172.16.2.0 [110/84] via 172.16.0.254, 00:16:15, Serial1/0
10.0.0.0/24 is subnetted, 3 subnets
C 10.2.0.0 is directly connected, FastEthernet0/0
O 10.2.1.0 [110/74] via 172.16.0.254, 02:42:10, Serial1/0
O E1 10.2.3.0 [110/84] via 172.16.0.254, 00:16:15, Serial1/0
O E1 192.168.0.0/22 [110/84] via 172.16.0.254, 00:02:26, Serial1/0
まとめ
Dynagen、Dynamips を使って、OSPF を練習しました。
Type4 LSA、スタブエリア、NSSAエリアについては次回に回します。
DR選定、Type2 LSA については、折りをみて。
Discussion