D.Horiyama's output

CCNA試験対策 ch17 IP Routing in the LAN

CCNAネットワーク勉強メモ

VLAN Routing with Router 802.1Q Trunks

  • いくつかのつなぎ方がある

    • routerとswitchをVLAN1つごとにケーブル1本で接続
    • あまりやらない
    • ROAS: router-on-a-stick
    • routerとLANスイッチをtrunkで接続
    • L3 switch with SVI: Switched Virtual Interfaces
    • L3 switch with routed interfaces

Configuring ROAS

20200505085015

  • ROAS: router-on-a-stick

    • router-switch間の物理接続は1本
    • 複数のVLANをtrunk接続
  • switchのVLANと、switch-router間のtrunk linkを構成する
Switch#configure 
Configuring from terminal, memory, or network [terminal]? 
Enter configuration commands, one per line.  End with CNTL/Z.
Switch(config)#
Switch(config)#int
Switch(config)#interface f0/11
Switch(config-if)#switchport access vlan 10
% Access VLAN does not exist. Creating vlan 10
Switch(config-if)#int f0/12
Switch(config-if)#switchport access vlan 20
% Access VLAN does not exist. Creating vlan 20
Switch(config-if)#int g0/1
Switch(config-if)#switchport mode trunk
Switch(config-if)#
Switch(config-if)#end
Switch#
%SYS-5-CONFIG_I: Configured from console by console

Switch#
%LINK-5-CHANGED: Interface GigabitEthernet0/1, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up

  • router側設定

    • vlan-idを添えてsubinterfaceのコンフィグを設定する
Router#configure terminal 
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#
Router(config)#int g0/0/0
Router(config-if)#no shutdown

Router(config-if)#
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/0, changed state to up

Router(config-if)#
Router(config-if)#int g0/0/0.10
Router(config-subif)#
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0.10, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/0.10, changed state to up

Router(config-subif)#encapsulation dot1q 10
Router(config-subif)#ip address 10.0.10.1 255.255.255.0
Router(config-subif)#
Router(config-subif)#int g0/0/0.20
Router(config-subif)#
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0.20, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/0.20, changed state to up

Router(config-subif)#encapsulation dot1q 20
Router(config-subif)#ip address 10.0.20.1 255.255.255.0
Router(config-subif)#end
Router#
%SYS-5-CONFIG_I: Configured from console by console

Router#
  • native VLANのときはencapsulation dot1q vlan-id nativeを使用する
  • 疎通確認
C:\>ping 0.0.0.0

Pinging 0.0.0.0 with 32 bytes of data:

Reply from 10.0.10.1: bytes=32 time<1ms TTL=255
Reply from 10.0.10.1: bytes=32 time<1ms TTL=255
Reply from 10.0.10.1: bytes=32 time<1ms TTL=255
Reply from 10.0.10.1: bytes=32 time=1ms TTL=255

Ping statistics for 0.0.0.0:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 1ms, Average = 0ms

C:\>ping 10.0.20.11

Pinging 10.0.20.11 with 32 bytes of data:

Reply from 10.0.20.11: bytes=32 time=1ms TTL=127
Reply from 10.0.20.11: bytes=32 time<1ms TTL=127
Reply from 10.0.20.11: bytes=32 time=1ms TTL=127
Reply from 10.0.20.11: bytes=32 time<1ms TTL=127

Ping statistics for 10.0.20.11:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 1ms, Average = 0ms

Verifying ROAS

Router>show ip route
Codes: L - local, 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, E - EGP
       i - IS-IS, 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

     10.0.0.0/8 is variably subnetted, 4 subnets, 2 masks
C       10.0.10.0/24 is directly connected, GigabitEthernet0/0/0.10
L       10.0.10.1/32 is directly connected, GigabitEthernet0/0/0.10
C       10.0.20.0/24 is directly connected, GigabitEthernet0/0/0.20
L       10.0.20.1/32 is directly connected, GigabitEthernet0/0/0.20

Router>
Router#show ip interface brief | include 0/0
GigabitEthernet0/0/0   unassigned      YES unset  up                    up 
GigabitEthernet0/0/0.1010.0.10.1       YES manual up                    up 
GigabitEthernet0/0/0.2010.0.20.1       YES manual up                    up 
GigabitEthernet0/0/1   unassigned      YES unset  administratively down down 
GigabitEthernet0/0/2   unassigned      YES unset  administratively down down 
Router#

  • show vlansコマンドが使えるはずだがPacket Tracerでは動作せず…

    • どのtrunk interfaceがどのVLANを使っているか
    • どのVLANがnative VLANか
    • パケット統計情報

Troubleshooting ROAS

  • 確認事項

    • nativeでないVLANをsubinterfaceでencapsulation dot1q vlan-idで設定しているか
    • show interfaces trunk
    • VLANが確かにtrunkに含まれているか
    • VTP(VLAN Trunking Protocol)で枝切りされていたり、STPでブロックされていないか
    • 各subinterfaceにIPアドレスを付与したか
    • native LANをsubinterfaceでencapsulation dot1q vlan-id native、もしくは物理interfaceで設定しているか
    • switch側のtrunk設定のnative VLANと、router側のnative VLAN設定が一致しているか
    • ちゃんとno shutdownしているか

VLAN Routing with Layer 3 Switch SVIs

Configuring Routing Using Switch SVIs

20200505085101

  • L3 Switch

    • SVI: Switched Virtual Interfaces をもつ
    • routerのinterface同様、IPアドレスとマスクをもつinterface
    • IP routing tableをもつ
  • VLANを作り、interfaceにIPアドレスを振る
Switch#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Switch(config)#
Switch(config)#ip routing
Switch(config)#interface vlan 10
Switch(config-if)#ip address 10.1.10.1 255.255.255.0
Switch(config-if)#
Switch(config-if)#interface vlan 20
Switch(config-if)#ip address 10.1.20.1 255.255.255.0
Switch(config-if)#
Switch(config-if)#interface vlan 30
Switch(config-if)#ip address 10.1.30.1 255.255.255.0
Switch(config-if)#
  • 各interfaceをvlanに割り当てる
Switch(config-if)#interface f0/11
Switch(config-if)#switchport access vlan 10
% Access VLAN does not exist. Creating vlan 10
Switch(config-if)#
%LINK-5-CHANGED: Interface Vlan10, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan10, changed state to up

Switch(config-if)#
Switch(config-if)#interface f0/12
Switch(config-if)#switchport access vlan 20
% Access VLAN does not exist. Creating vlan 20
Switch(config-if)#
%LINK-5-CHANGED: Interface Vlan20, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan20, changed state to up

Switch(config-if)#
Switch(config-if)#interface f0/13
Switch(config-if)#switchport access vlan 30
% Access VLAN does not exist. Creating vlan 30
Switch(config-if)#
%LINK-5-CHANGED: Interface Vlan30, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan30, changed state to up

Switch(config-if)#
Switch(config-if)#end
Switch#
%SYS-5-CONFIG_I: Configured from console by console

Switch#
Switch#show interfaces status
Port      Name               Status       Vlan       Duplex  Speed Type
Fa0/1                        notconnect   1          auto    auto  10/100BaseTX
Fa0/2                        notconnect   1          auto    auto  10/100BaseTX
Fa0/3                        notconnect   1          auto    auto  10/100BaseTX
Fa0/4                        notconnect   1          auto    auto  10/100BaseTX
Fa0/5                        notconnect   1          auto    auto  10/100BaseTX
Fa0/6                        notconnect   1          auto    auto  10/100BaseTX
Fa0/7                        notconnect   1          auto    auto  10/100BaseTX
Fa0/8                        notconnect   1          auto    auto  10/100BaseTX
Fa0/9                        notconnect   1          auto    auto  10/100BaseTX
Fa0/10                       notconnect   1          auto    auto  10/100BaseTX
Fa0/11                       connected    10         auto    auto  10/100BaseTX
Fa0/12                       connected    20         auto    auto  10/100BaseTX
Fa0/13                       connected    30         auto    auto  10/100BaseTX
Fa0/14                       notconnect   1          auto    auto  10/100BaseTX
Fa0/15                       notconnect   1          auto    auto  10/100BaseTX
Fa0/16                       notconnect   1          auto    auto  10/100BaseTX
Fa0/17                       notconnect   1          auto    auto  10/100BaseTX
Fa0/18                       notconnect   1          auto    auto  10/100BaseTX
Fa0/19                       notconnect   1          auto    auto  10/100BaseTX
Fa0/20                       notconnect   1          auto    auto  10/100BaseTX
Fa0/21                       notconnect   1          auto    auto  10/100BaseTX
Fa0/22                       notconnect   1          auto    auto  10/100BaseTX
Fa0/23                       notconnect   1          auto    auto  10/100BaseTX
Fa0/24                       notconnect   1          auto    auto  10/100BaseTX
Gig0/1                       notconnect   1          auto    auto  10/100BaseTX
Gig0/2                       notconnect   1          auto    auto  10/100BaseTX
  • 疎通確認
  • 10.1.10.0/24の10.1.10.11 から
C:\>ping 0.0.0.0

Pinging 0.0.0.0 with 32 bytes of data:

Reply from 10.1.10.1: bytes=32 time<1ms TTL=255
Reply from 10.1.10.1: bytes=32 time<1ms TTL=255
Reply from 10.1.10.1: bytes=32 time<1ms TTL=255
Reply from 10.1.10.1: bytes=32 time<1ms TTL=255

Ping statistics for 0.0.0.0:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
  • 10.1.20.11, 10.1.30.11へ
C:\>ping 10.1.20.11

Pinging 10.1.20.11 with 32 bytes of data:

Request timed out.
Reply from 10.1.20.11: bytes=32 time=4ms TTL=127
Reply from 10.1.20.11: bytes=32 time=4ms TTL=127
Reply from 10.1.20.11: bytes=32 time=4ms TTL=127

Ping statistics for 10.1.20.11:
    Packets: Sent = 4, Received = 3, Lost = 1 (25% loss),
Approximate round trip times in milli-seconds:
    Minimum = 4ms, Maximum = 4ms, Average = 4ms

C:\>ping 10.1.30.11

Pinging 10.1.30.11 with 32 bytes of data:

Request timed out.
Reply from 10.1.30.11: bytes=32 time=4ms TTL=127
Reply from 10.1.30.11: bytes=32 time<1ms TTL=127
Reply from 10.1.30.11: bytes=32 time=4ms TTL=127

Ping statistics for 10.1.30.11:
    Packets: Sent = 4, Received = 3, Lost = 1 (25% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 4ms, Average = 2ms

Verifying Routing with SVIs

Switch#show ip route
Codes: C - connected, S - static, I - IGRP, 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, E - EGP
       i - IS-IS, 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

     10.0.0.0/24 is subnetted, 3 subnets
C       10.1.10.0 is directly connected, Vlan10
C       10.1.20.0 is directly connected, Vlan20
C       10.1.30.0 is directly connected, Vlan30

Troubleshooting Routing with SVIs

  • 確認事項

    • VLANを定義していること
    • VLANには少なくとも1本のup/up interfaceが含まれること
    • VTPで枝切りされたりSTPでblockingされていないこと
    • VLANのno shutdown
    • VLANに含まれているinterfaceのno shutdown
Switch#show ip interface brief | include Vlan
Vlan1                  unassigned      YES unset  administratively down down 
Vlan10                 10.1.10.1       YES manual up                    up 
Vlan20                 10.1.20.1       YES manual up                    up 
Vlan30                 10.1.30.1       YES manual up                    up

VLAN Routing with Layer 3 Switch Routed Ports

Implementing Routed Interfaces on Switches

20200505085124

  • 10.2.0.0/16のネットワークが別にあったケースを想定 (図左下)
Router(config)#interface g0/0/1
Router(config-if)#ip address 10.2.10.1 255.255.255.0
Router(config-if)#no shutdown

Router(config-if)#
Router(config-if)#
%LINK-5-CHANGED: Interface GigabitEthernet0/0/1, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/1, changed state to up
  • router - L3 switchをつなぐネットワーク10.10.0.0/16を作成
Router(config)#interface g0/0/0
Router(config-if)#no shutdown

Router(config-if)#
%LINK-5-CHANGED: Interface GigabitEthernet0/0/0, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/0/0, changed state to up
Router(config-if)#ip address 10.10.1.2 255.255.255.0
Switch#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Switch(config)#
Switch(config)#interface g0/1
Switch(config-if)#no switchport
Switch(config-if)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to down

%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up

Switch(config-if)#ip address 10.10.1.1 255.255.255.0
Switch(config-if)#
Switch(config-if)#end
Switch#
%SYS-5-CONFIG_I: Configured from console by console

Switch#
  • route table登録
  • L3 Switch
Switch(config)#ip route 10.2.0.0 255.255.0.0 g0/1
  • Router
Router(config)#ip route 10.1.0.0 255.255.0.0 g0/0/0
%Default route without gateway, if not a point-to-point interface, may impact performance

  • 疎通

    • 10.2.10.11 -> 10.1.10.11
C:\>ping 10.1.10.11

Pinging 10.1.10.11 with 32 bytes of data:

Reply from 10.1.10.11: bytes=32 time=8ms TTL=126

Ping statistics for 10.1.10.11:
    Packets: Sent = 1, Received = 1, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 8ms, Maximum = 8ms, Average = 8ms
  • 設定確認

  • Vlanがroutedになる

    • VLANじゃないので
Switch#show interface status
Port      Name               Status       Vlan       Duplex  Speed Type
Fa0/1                        notconnect   1          auto    auto  10/100BaseTX
Fa0/2                        notconnect   1          auto    auto  10/100BaseTX
Fa0/3                        notconnect   1          auto    auto  10/100BaseTX
Fa0/4                        notconnect   1          auto    auto  10/100BaseTX
Fa0/5                        notconnect   1          auto    auto  10/100BaseTX
Fa0/6                        notconnect   1          auto    auto  10/100BaseTX
Fa0/7                        notconnect   1          auto    auto  10/100BaseTX
Fa0/8                        notconnect   1          auto    auto  10/100BaseTX
Fa0/9                        notconnect   1          auto    auto  10/100BaseTX
Fa0/10                       notconnect   1          auto    auto  10/100BaseTX
Fa0/11                       connected    10         auto    auto  10/100BaseTX
Fa0/12                       connected    20         auto    auto  10/100BaseTX
Fa0/13                       connected    30         auto    auto  10/100BaseTX
Fa0/14                       notconnect   1          auto    auto  10/100BaseTX
Fa0/15                       notconnect   1          auto    auto  10/100BaseTX
Fa0/16                       notconnect   1          auto    auto  10/100BaseTX
Fa0/17                       notconnect   1          auto    auto  10/100BaseTX
Fa0/18                       notconnect   1          auto    auto  10/100BaseTX
Fa0/19                       notconnect   1          auto    auto  10/100BaseTX
Fa0/20                       notconnect   1          auto    auto  10/100BaseTX
Fa0/21                       notconnect   1          auto    auto  10/100BaseTX
Fa0/22                       notconnect   1          auto    auto  10/100BaseTX
Fa0/23                       notconnect   1          auto    auto  10/100BaseTX
Fa0/24                       notconnect   1          auto    auto  10/100BaseTX
Gig0/1                       connected    routed     auto    auto  10/100BaseTX
Gig0/2                       notconnect   1          auto    auto  10/100BaseTX
  • Switchport: Disabled になるはずだがPacket TracerだからかEnabledだった
Switch#show interfaces g0/1 switchport
Name: Gig0/1
Switchport: Enabled
...

  • SVIとrouted interfaceどちらを使う？

    • 両方
    • core/distribution/access デザインでは…
    • L3 distribution/coreはrouted interface
    • L2 accessはSVI

Implementing Layer 3 EtherChannels

20200505085213

  • no switchportしつつEtherChannel

  • PCに面している側: SVI (L2)

    • VLANにIPアドレスを振る
L3SW2(config)#
L3SW2(config)#interface f0/11
L3SW2(config-if)#switchport access vlan 3
% Access VLAN does not exist. Creating vlan 3
L3SW2(config-if)#interface vlan 3
L3SW2(config-if)#
%LINK-5-CHANGED: Interface Vlan3, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan3, changed state to up

L3SW2(config-if)#
L3SW2(config-if)#ip address 10.1.3.1 255.255.255.0
L3SW2(config-if)#
  • 別のL3SWに面している側: 2本の routed portをEtherChannelでまとめる (L3 EtherChannel)
  • L3なのでinterfaceにIPアドレスを振る
L3SW2(config-if)#interface range g0/1-2
L3SW2(config-if-range)#no switchport
L3SW2(config-if-range)#no ip address
L3SW2(config-if-range)#channel-group 12 mode on
L3SW2(config-if-range)#
Creating a port-channel interface Port-channel 12

%LINK-5-CHANGED: Interface Port-channel12, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface Port-channel12, changed state to up

L3SW2(config-if-range)#
L3SW2(config-if-range)#interface port-channel 12
L3SW2(config-if)#ip address 10.1.12.2 255.255.255.0
L3SW2(config-if)#
L3SW2(config-if)#exit

  • route設定(static)

    • ip routing を指定しないと、コンフィグを記述してもroute tableにエントリが現れないことに注意する
L3SW2(config)#ip routing
L3SW2(config)#
L3SW2(config)#ip route 10.1.2.0 255.255.255.0 10.1.12.1
L3SW2(config)#
L3SW2(config)#end
L3SW2#
%SYS-5-CONFIG_I: Configured from console by console
  • route確認
L3SW2#show ip route
Codes: C - connected, S - static, I - IGRP, 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, E - EGP
       i - IS-IS, 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

     10.0.0.0/24 is subnetted, 3 subnets
S       10.1.2.0 [1/0] via 10.1.12.1
C       10.1.3.0 is directly connected, Vlan3
C       10.1.12.0 is directly connected, Port-channel12

L3SW2#
  • 疎通確認
C:\>ping 10.1.3.11

Pinging 10.1.3.11 with 32 bytes of data:

Reply from 10.1.3.11: bytes=32 time=6ms TTL=126
Reply from 10.1.3.11: bytes=32 time<1ms TTL=126

Ping statistics for 10.1.3.11:
    Packets: Sent = 2, Received = 2, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 6ms, Average = 3ms

Control-C
^C
C:\>ping 0.0.0.0

Pinging 0.0.0.0 with 32 bytes of data:

Reply from 10.1.2.1: bytes=32 time<1ms TTL=255

Ping statistics for 0.0.0.0:
    Packets: Sent = 1, Received = 1, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

Control-C
^C
C:\>