ルート制御 その3

ネットワーク構成

route_control_01.png
ルート制御 ネットワーク構成

設定概要

各ルータのルーティングに関する設定は次のとおりです。

R1

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
interface Ethernet0/0
ip address 192.168.12.1 255.255.255.0
!
interface Ethernet0/1
ip address 192.168.13.1 255.255.255.0
!
interface Ethernet0/2
ip address 192.168.14.1 255.255.255.0
!
interface Ethernet0/3
ip address 192.168.15.1 255.255.255.0
!
interface Ethernet1/0
ip address 192.168.16.1 255.255.255.0
!
interface Ethernet1/1
ip address 192.168.17.1 255.255.255.0
!
router eigrp 1
network 192.168.16.0
network 192.168.17.0
no auto-summary
!
router ospf 1
router-id 1.1.1.1
log-adjacency-changes
network 192.168.14.0 0.0.0.255 area 0
network 192.168.15.0 0.0.0.255 area 0
!
router rip
version 2
network 192.168.12.0
network 192.168.13.0
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

R2

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
interface Ethernet0/0
ip address 192.168.12.2 255.255.255.0
!
interface Ethernet0/1
ip address 192.168.28.2 255.255.255.0
!
router rip
version 2
network 192.168.12.0
network 192.168.28.0
no auto-summary
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

R3

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
interface Ethernet0/0
ip address 192.168.13.3 255.255.255.0
!
interface Ethernet0/1
ip address 192.168.38.3 255.255.255.0
!
router rip
version 2
network 192.168.13.0
network 192.168.38.0
no auto-summary
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

R4

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
interface Ethernet0/0
ip address 192.168.14.4 255.255.255.0
!
interface Ethernet0/1
ip address 192.168.48.4 255.255.255.0
!
router ospf 1
router-id 4.4.4.4
log-adjacency-changes
network 192.168.0.0 0.0.255.255 area 0
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

R5

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
interface Ethernet0/0
ip address 192.168.15.5 255.255.255.0
!
interface Ethernet0/1
ip address 192.168.58.5 255.255.255.0
!
router ospf 1
router-id 5.5.5.5
log-adjacency-changes
network 192.168.0.0 0.0.255.255 area 0
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

R6

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
interface Ethernet0/0
ip address 192.168.16.6 255.255.255.0
!
interface Ethernet0/1
ip address 192.168.68.6 255.255.255.0
!
router eigrp 1
network 192.168.0.0 0.0.255.255
no auto-summary
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

R7

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
interface Ethernet0/0
ip address 192.168.17.7 255.255.255.0
!
interface Ethernet0/1
ip address 192.168.78.7 255.255.255.0
!
router eigrp 1
network 192.168.0.0 0.0.255.255
no auto-summary
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

R8

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
interface Loopback0
ip address 192.168.2.8 255.255.255.0 secondary
ip address 192.168.4.8 255.255.255.0 secondary
ip address 192.168.6.8 255.255.255.0 secondary
ip address 192.168.1.8 255.255.255.0
ip ospf network point-to-point
!
interface Loopback3
ip address 192.168.3.8 255.255.255.0
ip ospf network point-to-point
!
interface Loopback5
ip address 192.168.5.8 255.255.255.0
ip ospf network point-to-point
!
interface Ethernet0/0
ip address 192.168.28.8 255.255.255.0
!
interface Ethernet0/1
ip address 192.168.38.8 255.255.255.0
!
interface Ethernet0/2
ip address 192.168.48.8 255.255.255.0
!
interface Ethernet0/3
ip address 192.168.58.8 255.255.255.0
!
interface Ethernet1/0
ip address 192.168.68.8 255.255.255.0
!
interface Ethernet1/1
ip address 192.168.78.8 255.255.255.0
!
router eigrp 1
network 192.168.1.0
network 192.168.2.0
network 192.168.3.0
network 192.168.4.0
network 192.168.5.0
network 192.168.6.0
network 192.168.68.0
network 192.168.78.0
no auto-summary
!
router ospf 1
router-id 8.8.8.8
log-adjacency-changes
network 192.168.1.0 0.0.0.255 area 0
network 192.168.2.0 0.0.0.255 area 0
network 192.168.3.0 0.0.0.255 area 0
network 192.168.4.0 0.0.0.255 area 0
network 192.168.5.0 0.0.0.255 area 0
network 192.168.6.0 0.0.0.255 area 0
network 192.168.48.0 0.0.0.255 area 0
network 192.168.58.0 0.0.0.255 area 0
!
router rip
version 2
network 192.168.1.0
network 192.168.2.0
network 192.168.3.0
network 192.168.4.0
network 192.168.5.0
network 192.168.6.0
network 192.168.28.0
network 192.168.38.0
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

GNS3プロジェクトダウンロード(MM_1235_route_control03_init.zip)

問題

R1のルーティングテーブルで192.168.5.0/24と192.168.6.0/24がEIGRPルートとして次のように見えるようにしてください。

R1

----------------------------------------------------
R1#show ip route eigrp
D    192.168.5.0/24 [90/435200] via 192.168.17.7, 00:00:34, Ethernet1/1
D    192.168.6.0/24 [90/435200] via 192.168.16.6, 00:00:28, Ethernet1/0
----------------------------------------------------

※ 上記の出力はEIGRPルートの抜粋です

解答

R1

----------------------------------------------------
router eigrp 1
offset-list 5 in 100 Ethernet1/0
offset-list 6 in 100 Ethernet1/1
!
access-list 5 permit 192.168.5.0
access-list 6 permit 192.168.6.0
----------------------------------------------------

GNS3プロジェクトダウンロード(MM_1235_route_control03_comp.zip)

ワンポイント

  • EIGRPでは、オフセットリストによって送受信するルートのメトリックを増加させることができる。

解説

192.168.5.0/24と192.168.6.0/24は等コストロードバランスのEIGRPルートとしてルーティングテーブルに登録されています。等コストロードバランスでなくなるようにするために、オフセットリストによってメトリックを調整します。

R1

----------------------------------------------------
router eigrp 1
offset-list 5 in 100 Ethernet1/0
offset-list 6 in 100 Ethernet1/1
!
access-list 5 permit 192.168.5.0
access-list 6 permit 192.168.6.0
----------------------------------------------------

オフセットリストの設定後、EIGRPのルート制御を確認します。show ip protocolsコマンドでオフセットリストの適用を確認することができます。また、show ip eigrp toplogyでオフセットリストによってメトリックが増加していることがわかります。そして、ルーティングテーブルを見ると、条件通りに192.168.5.0/24と192.168.6.0/24のルートが登録されています。

R1

----------------------------------------------------
R1#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
Incoming routes in Ethernet1/0 will have 100 added to metric if on list 5
Incoming routes in Ethernet1/1 will have 100 added to metric if on list 6
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:
192.168.16.0
192.168.17.0
Routing Information Sources:
Gateway         Distance      Last Update
192.168.16.6          90      00:07:08
192.168.17.7          90      00:07:08
Distance: internal 90 external 170
Routing Protocol is "ospf 1"
~省略~
Routing Protocol is "rip"
~省略~
R1#show ip eigrp 1 topology
IP-EIGRP Topology Table for AS(1)/ID(192.168.19.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
~省略~
P 192.168.5.0/24, 1 successors, FD is 435200
via 192.168.17.7 (435200/409600), Ethernet1/1
via 192.168.16.6 (435300/409700), Ethernet1/0
P 192.168.6.0/24, 1 successors, FD is 435200
via 192.168.16.6 (435200/409600), Ethernet1/0
via 192.168.17.7 (435300/409700), Ethernet1/1
~省略~
R1#show ip route eigrp
D    192.168.78.0/24 [90/307200] via 192.168.17.7, 00:01:06, Ethernet1/1
D    192.168.4.0/24 [90/435200] via 192.168.17.7, 00:01:06, Ethernet1/1
[90/435200] via 192.168.16.6, 00:01:06, Ethernet1/0
D    192.168.5.0/24 [90/435200] via 192.168.17.7, 00:00:07, Ethernet1/1
D    192.168.6.0/24 [90/435200] via 192.168.16.6, 00:00:07, Ethernet1/0
D    192.168.68.0/24 [90/307200] via 192.168.16.6, 00:01:06, Ethernet1/0
D    192.168.1.0/24 [90/435200] via 192.168.17.7, 00:01:06, Ethernet1/1
[90/435200] via 192.168.16.6, 00:01:06, Ethernet1/0
D    192.168.2.0/24 [90/435200] via 192.168.17.7, 00:01:06, Ethernet1/1
[90/435200] via 192.168.16.6, 00:01:06, Ethernet1/0
D    192.168.3.0/24 [90/435200] via 192.168.17.7, 00:01:06, Ethernet1/1
[90/435200] via 192.168.16.6, 00:01:06, Ethernet1/0
----------------------------------------------------

Follow me!