요약
네트워크 장비 관점에서 통신이 되는 과정을 설명한다.
기술 스택
1. VLAN
2. OSPF
3. HSRP
4. PVST
구성도
1호기 설정
SW1#show run
Building configuration...
Current configuration : 2164 bytes
!
version 16.3.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname SW1
!
!
!
!
!
!
!
ip cef
ip routing
!
no ipv6 cef
!
!
!
!
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
spanning-tree vlan 10 priority 8192
spanning-tree vlan 20 priority 24576
!
!
!
!
!
!
interface Loopback0
ip address 1.1.1.1 255.255.255.255
!
interface GigabitEthernet1/0/1
switchport mode trunk
switchport nonegotiate
!
interface GigabitEthernet1/0/2
switchport mode trunk
switchport nonegotiate
!
interface GigabitEthernet1/0/3
switchport mode trunk
!
interface GigabitEthernet1/0/4
no switchport
ip address 192.168.100.10 255.255.255.252
duplex auto
speed auto
!
!
!
interface Vlan1
no ip address
shutdown
!
interface Vlan10
mac-address 0010.1127.0301
ip address 192.168.10.253 255.255.255.0
standby 1 ip 192.168.10.1
standby 1 priority 105
standby 1 preempt
!
interface Vlan20
mac-address 0010.1127.0302
ip address 192.168.20.254 255.255.255.0
standby 2 ip 192.168.20.1
standby 2 priority 105
standby 2 preempt
!
router ospf 10
log-adjacency-changes
redistribute connected subnets
network 192.168.100.8 0.0.0.3 area 0
!
ip classless
!
ip flow-export version 9
!
end
2호기 설정
SW2#show run
Building configuration...
Current configuration : 2066 bytes
!
version 16.3.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname SW2
!
!
!
!
!
!
!
no ip cef
ip routing
!
no ipv6 cef
!
!
!
!
!
!
!
!
!
!
!
!
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface Loopback0
ip address 2.2.2.2 255.255.255.255
!
interface GigabitEthernet1/0/1
switchport mode trunk
switchport nonegotiate
!
interface GigabitEthernet1/0/2
switchport mode trunk
switchport nonegotiate
!
interface GigabitEthernet1/0/3
switchport mode trunk
!
interface GigabitEthernet1/0/4
no switchport
ip address 192.168.100.9 255.255.255.252
ip ospf priority 10
duplex auto
speed auto
!
interface Vlan1
no ip address
shutdown
!
interface Vlan10
mac-address 000d.bd0e.8d01
ip address 192.168.10.254 255.255.255.0
standby 1 ip 192.168.10.1
standby 1 preempt
!
interface Vlan20
mac-address 000d.bd0e.8d02
ip address 192.168.20.253 255.255.255.0
standby 2 ip 192.168.20.1
standby 2 preempt
!
router ospf 10
log-adjacency-changes
redistribute connected subnets
network 192.168.100.8 0.0.0.3 area 0
!
ip classless
!
ip flow-export version 9
!
!
!
end3호기 설정
show run
Building configuration...
Current configuration : 1174 bytes
!
version 15.0
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname SW3
!
!
!
!
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
interface FastEthernet0/1
switchport access vlan 10
switchport mode access
!
interface GigabitEthernet0/1
switchport mode trunk
!
interface GigabitEthernet0/2
switchport mode trunk
!
interface Vlan1
no ip address
shutdown
!
!
end
4호기 설정
SW4#show run
Building configuration...
Current configuration : 1174 bytes
!
version 15.0
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname SW4
!
!
!
!
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
interface FastEthernet0/1
switchport access vlan 20
switchport mode access
!
interface GigabitEthernet0/1
switchport mode trunk
!
interface GigabitEthernet0/2
switchport mode trunk
!
interface Vlan1
no ip address
shutdown
!
!
!
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
!
end
확인사항
PC0(192.168.10.10) <-> PC1(192.168.20.10) 통신 경로 확인
PC0 에서 ping 192.168.20.10 쳤을때..
PC0 라우팅 테이블 확인
C:\>netstat -r
Route Table
===========================================================================
Interface List
0x1 ........................... PT TCP Loopback interface
0x2 ...00 16 6f 0d 88 ec ...... PT Ethernet interface
0x1 ........................... PT TCP Loopback interface
0x2 ...00 16 6f 0d 88 ec ...... PT Bluetooth interface
===========================================================================
===========================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 192.168.10.1 192.168.10.10 1
Default Gateway: 192.168.10.1
===========================================================================
Persistent Routes:
None
192.168.20.10 은 인터페이스에 할당된 네트워크 대역이 달라서 게이트웨이 IP로 전송
arp 테이블 게이트웨이 IP MAC 주소 확인
C:\>arp -a
Internet Address Physical Address Type
192.168.10.1 0000.0c07.ac01 dynamic출발지 MAC 주소(인터페이스 MAC)
0060.5c28.64ae
목적지 MAC 주소(게이트웨이 MAC)
0000.0c07.ac01
출발지 IP 주소
192.168.10.10
목적지 IP 주소
192.168.20.10
패킷 완성 자기 인터페이스(NIC 카드)로 전송
3호기 스위치 MAC table 확인
SW3#show mac address-table
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
1 0002.164e.3201 DYNAMIC Gig0/1
1 0090.21b4.5902 DYNAMIC Gig0/2
10 0002.164e.3201 DYNAMIC Gig0/1
10 0010.1127.0301 DYNAMIC Gig0/1
10 0060.5c28.64ae DYNAMIC Fa0/1
20 0002.164e.3201 DYNAMIC Gig0/1
20 0010.1127.0302 DYNAMIC Gig0/1
30 0002.164e.3201 DYNAMIC Gig0/1
30 0090.21b4.5902 DYNAMIC Gig0/2
40 0002.164e.3201 DYNAMIC Gig0/1
40 0090.21b4.5902 DYNAMIC Gig0/2목적지 MAC 주소에 해당되는 포트가 없으므로 수신한 포트 제외한 나머지 포트로 플로딩(뿌리기)
Gig0/1 , Gig0/2
트렁크 포트(태그포트) 로 설정된 포트로 나갈때는 VLAN ID 를 붙이고 플로딩 됨
1호기 패킷 수신 후 VLAN ID 확인
VLAN 10 에서 목적지 MAC 주소가 자기 자신에 MAC 주소 인거 확인 후 IP 확인
1호기(SW1) 라우팅 테이블 확인
SW1#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
1.0.0.0/32 is subnetted, 1 subnets
C 1.1.1.1 is directly connected, Loopback0
2.0.0.0/32 is subnetted, 1 subnets
O E2 2.2.2.2 [110/20] via 192.168.100.9, 00:59:19, GigabitEthernet1/0/4
C 192.168.10.0/24 is directly connected, Vlan10
C 192.168.20.0/24 is directly connected, Vlan20
192.168.100.0/30 is subnetted, 1 subnets
C 192.168.100.8 is directly connected, GigabitEthernet1/0/4
connected로 된 192.168.20.0/24 경로 매치 (라우팅)
라우팅 경로가 VLAN 20 으로 되있음, arp 테이블 확인
SW1#show ip arp
Protocol Address Age (min) Hardware Addr Type Interface
Internet 192.168.10.1 35 0000.0C07.AC01 ARPA Vlan10
Internet 192.168.10.10 31 0060.5C28.64AE ARPA Vlan10
Internet 192.168.10.253 - 0010.1127.0301 ARPA Vlan10
Internet 192.168.20.10 36 0090.2B7D.7CA3 ARPA Vlan20
Internet 192.168.20.253 36 000D.BD0E.8D02 ARPA Vlan20
Internet 192.168.20.254 - 0010.1127.0302 ARPA Vlan20
Internet 192.168.100.9 36 0090.21B4.5904 ARPA GigabitEthernet1/0/4
Internet 192.168.100.10 - 0002.164E.3204 ARPA GigabitEthernet1/0/4VLAN20 에 해당 목적지 IP에 192.168.20.10 에 대한 MAC 주소가 있으므로
출발지 MAC
0060.5c28.64ae
목적지 MAC(변경)
0090.2B7D.7CA3
출발지 IP
192.168.10.10
목적지 IP
192.168.20.10
으로 패킷 만들고 mac 테이블 확인
SW1#show mac address-table
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
1 00d0.ff6a.0a19 DYNAMIC Gig1/0/2
10 0060.5c28.64ae DYNAMIC Gig1/0/1
20 0090.2b7d.7ca3 DYNAMIC Gig1/0/2
30 00d0.ff6a.0a19 DYNAMIC Gig1/0/2
40 00d0.ff6a.0a19 DYNAMIC Gig1/0/2VLAN 20 에 해당되는 포트 중에 MAC 목적지 MAC 주소와 일치하는 포트로 패킷을 포워딩한다.
Gig1/0/2로 전송
4호기 스위치
SW4#show mac address-table
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
1 0002.164e.3202 DYNAMIC Gig0/1
1 0090.21b4.5901 DYNAMIC Gig0/2
10 0002.164e.3202 DYNAMIC Gig0/1
10 0010.1127.0301 DYNAMIC Gig0/1
20 0002.164e.3202 DYNAMIC Gig0/1
20 0010.1127.0302 DYNAMIC Gig0/1
20 0090.2b7d.7ca3 DYNAMIC Fa0/1
30 0090.21b4.5901 DYNAMIC Gig0/2
40 0090.21b4.5901 DYNAMIC Gig0/2목적지 MAC 주소와 일치하는 포트 Fa0/1 인거 확인
Fa0/1 로 패킷 포워딩
PC1
C:\>netstat -r
Route Table
===========================================================================
Interface List
0x1 ........................... PT TCP Loopback interface
0x2 ...00 16 6f 0d 88 ec ...... PT Ethernet interface
0x1 ........................... PT TCP Loopback interface
0x2 ...00 16 6f 0d 88 ec ...... PT Bluetooth interface
===========================================================================
===========================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 192.168.20.1 192.168.20.10 1
Default Gateway: 192.168.20.1
===========================================================================
Persistent Routes:
None
PC1은 자기 자신의 MAC 주소인거 확인하고 IP 확인 내 IP 인거 확인 하고 ICMP 프로토콜(Ping) 처리 Reply 전송
반대도 똑같은 통신과정을 통해 Ping 성공이 됨
Request , Reply 둘 다 문제 없어야지 ping 성공
마무리
패킷트레이서를 이용하여 PC0 에서 PC1 로 스위치, 라우터 관점에서 통신이 되는 과정을 확인
