2025 Security engineer Bootcamp/2. 네트워크 개요

네트워크 실습(Packet Tracer[Cisco])

Hoon`ss 2025. 9. 30. 15:01

1. Switch 기본 설정

네트워크 장비에 처음 접근하여 기본적인 환경을 설정하는 과정입니다.

Cisco IOS 모드

Cisco 장비는 다음과 같은 주요 설정 모드를 가집니다. 각 모드마다 실행할 수 있는 명령어가 다릅니다.

 
  • 사용자 모드 (User Mode): Router> 프롬프트로 표시되며, 장비의 상태 확인 등 제한적인 작업만 가능합니다.
  • 관리자 모드 (Privileged Mode): Router# 프롬프트로 표시되며, enable 명령어로 진입합니다. 장비의 모든 설정을 조회하고 테스트를 수행할 수 있습니다.
  • 전역 설정 모드 (Global Configuration Mode): Router(config)# 프롬프트로 표시되며, configure terminal 명령어로 진입합니다. 장비의 전반적인 설정을 변경할 수 있습니다.
  • 인터페이스 설정 모드 (Interface Configuration Mode): Router(config-if)# 프롬프트로 표시되며, 특정 인터페이스에 대한 세부 설정을 진행합니다.

 

주요 기본 명령어

  • 호스트 이름 변경
  •   
    Switch(config)# hostname DSW11
  • Bash
     
  • 패스워드 설정

    •  
    • enable password: 패스워드가 암호화되지 않은 채로 저장됩니다.

    •  
    • enable secret: 패스워드가 암호화되어 저장되며, enable password보다 우선순위가 높습니다.
    Bash
     
    Switch(config)# enable secret [패스워드]
  • 설정 저장 및 초기화
    • 현재 실행 중인 설정을 부팅 시 사용될 설정으로 영구 저장합니다.
    • Bash
       
      Switch# copy running-config startup-config
    • 저장된 부팅 설정을 삭제하여 장비를 초기화합니다 (reload 필요).
    • Bash
       
      Switch# erase startup-config
Switch# reload

 

Switch의 VLAN 설정 과정

 

1. VLAN 생성

Switch > enable

Switch # configure terminal

Switch(config) # vlan VLAN_번호

Switch(config-vlan) # name VLAN_설명

Switch(config-vlan) # exit

 

2. VLAN에 Port 가입

Switch > enable

Switch # configure terminal

Switch(config) # interface INTERFACE_번호

Switch(config-if) # switchport mode access

Switch(config-if) # switchport access vlan VLAN_번호

Switch(config-if) # exit

 

3. Inter-VLAN 통신을 위한 Router 설정

Router> enable

Router# configure terminal

Router(config)# interface fa0/0

Router(config-if)# ip address   IP주소   SUBNET_MASK

Router(config-if)# no shutdown

Router(config-if)# exit

 

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

192.168.10.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.10.0/24 is directly connected, FastEthernet0/0

L 192.168.10.254/32 is directly connected, FastEthernet0/0

192.168.20.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.20.0/24 is directly connected, FastEthernet0/1

L 192.168.20.254/32 is directly connected, FastEthernet0/1

 

Switch VLAN Trunk Port 설정

Switch(config) # interface INTERFACE_번호

Switch(config-if)# switchport mode trunk

Switch(config-if)# exit

 

Router의 Trunk Port 설정
Switch(config) # interface fa0/0

Switch(config-if) # no shutdown

Switch(config-if) # exit

 

 (2) Sub Interface 설정 (VLAN 별)

Switch(config) # interface fa0/0.SUB_INTERFACE_NUM

Switch(config-subif) # encapsulation  dot1q  VLAN_번호

Switch(config-subif) # ip address IP주소 SUBNET_MASK

Switch(config-subif) # exit

 

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

192.168.10.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.10.0/24 is directly connected, FastEthernet0/0.10

L 192.168.10.254/32 is directly connected, FastEthernet0/0.10

192.168.20.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.20.0/24 is directly connected, FastEthernet0/0.20

L 192.168.20.254/32 is directly connected, FastEthernet0/0.20

Routing

Static Routing

 

 

Static Routing 구성 단계

1. Interface에 IP 주소 할당

Router>enable

Router#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#hostname R1

R1(config)#interface gi0/1

R1(config-if)#ip address 192.168.1.1 255.255.255.0

R1(config-if)#no ip address 192.168.1.1 255.255.255.0

R1(config-if)#ip address 192.168.1.1 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#

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

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

R1(config-if)#exit

R1(config)#interface gi0/0

R1(config-if)#ip address 10.0.0.1 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#

%LINK-5-CHANGED: Interface GigabitEthernet0/0, changed state to up

R1(config-if)#exit

 

R1#show ip route

 

Router>enable

Router#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#hostname R2

R2(config)#

R2(config)#interface gi0/1

R2(config-if)#ip address 192.168.2.1 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#

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

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

R2(config-if)#exit

R2(config)#

R2(config)#interface gi0/0

R2(config-if)#ip address 10.0.0.2 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#

%LINK-5-CHANGED: Interface GigabitEthernet0/0, changed state to up

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

R2(config-if)#exit

 

R1#show ip route

 

2. Static Routing 설정

 

Router(config) # ip route  NETWORK  SUBNET_MASK  NEXT_HOP_IP

Router(config) # ip route  NETWORK  SUBNET_MASK  INTERFACE

 

R1(config)#ip route 192.168.2.0 255.255.255.0 10.0.0.2

 

R2(config)#ip route 192.168.1.0 255.255.255.0 10.0.0.1

 

3. Routing Table 확인

 

R1#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, 2 subnets, 2 masks

C 10.0.0.0/24 is directly connected, GigabitEthernet0/0

L 10.0.0.1/32 is directly connected, GigabitEthernet0/0

192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.1.0/24 is directly connected, GigabitEthernet0/1

L 192.168.1.1/32 is directly connected, GigabitEthernet0/1

S 192.168.2.0/24 [1/0] via 10.0.0.2

 

R2#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, 2 subnets, 2 masks

C 10.0.0.0/24 is directly connected, GigabitEthernet0/0

L 10.0.0.2/32 is directly connected, GigabitEthernet0/0

S 192.168.1.0/24 [1/0] via 10.0.0.1

192.168.2.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.2.0/24 is directly connected, GigabitEthernet0/1

L 192.168.2.1/32 is directly connected, GigabitEthernet0/1

 

Static Routing 2

 

 

 

DCE(Data Communication Equipment)

 - Serial 통신 구간에서 Clock을 제공하는 장비

 

DTE(Data Terminal Equipment)

 - Serial 통신 구간에서 Clock을 제공받는 장비

 

1. Interface에 IP 주소 할당

 

Router(config)#hostname R1

R1(config)#interface gi0/0

R1(config-if)#ip address 203.230.7.1 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit

 

[참고] Serial Interface 설정

R1(config)# interface s0/2/0

R1(config-if)# ip address 203.230.7.1 255.255.255.0

R1(config-if)# clock rate CLOCK_RATE

    - Router의 Serial Interface가 DCE인 경우에만

R1(config-if)# no shutdown

R1(config-if)# exit

 

R1(config)# interface s0/2/0

R1(config-if)# ip address 203.230.7.1 255.255.255.0

R1(config-if)# clock rate 64000

R1(config-if)# no shutdown

R1(config-if)# exit

 

Router(config)#hostname R2

R2(config)#interface gi0/0

R2(config-if)#ip address 203.230.9.1 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#

R2(config)#interface s0/2/1

R2(config-if)#ip address 203.230.8.2 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#

R2(config)#interface s0/2/0

R2(config-if)#ip address 203.230.10.1 255.255.255.0

R2(config-if)#clock rate 64000

R2(config-if)#no shutdown

R2(config-if)#exit

 

Router(config)#hostname R3

R3(config)#interface gi0/0

R3(config-if)#ip address 203.230.11.1 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit

 

R3(config)#interface s0/2/1

R3(config-if)#ip address 203.230.10.2 255.255.255.0

R3(config-if)#no shutdown

 

2. Static Routing 설정

 

R1(config)#ip route 203.230.9.0 255.255.255.0 203.230.8.2

R1(config)#ip route 203.230.10.0 255.255.255.0 203.230.8.2

R1(config)#ip route 203.230.11.0 255.255.255.0 203.230.8.2

 

R2(config)#ip route 203.230.7.0 255.255.255.0 203.230.8.1

R2(config)#ip route 203.230.11.0 255.255.255.0 203.230.10.2

R3(config)#ip route 203.230.7.0 255.255.255.0 203.230.10.1

R3(config)#ip route 203.230.8.0 255.255.255.0 203.230.10.1

R3(config)#ip route 203.230.9.0 255.255.255.0 203.230.10.1

 

3. Routing Table 확인

 

Default Routing

 - Routing Table에서 목적지에 대한 경로를 비교하는 기본 원칙은 Longest Prefix Match

 - Stub Network의 경우 접근하고자 하는 모든 외부 네트워크에 대한 Routing Table 구성은 현실적으로 어려움.

 - 다른 모든 Routing 경로에 해당하지 않는 경우 패킷을 전달하는 경로를 Default Routing이라고 함.

 

 Router(config)# ip route 0.0.0.0 0.0.0.0  NEXT_HOP_IP

 Router(config)# ip route 0.0.0.0 0.0.0.0  INTERFACE



Default Routing으로 변경

R1(config)#no ip route 203.230.9.0 255.255.255.0 203.230.8.2

R1(config)#no ip route 203.230.10.0 255.255.255.0 203.230.8.2

R1(config)#no ip route 203.230.11.0 255.255.255.0 203.230.8.2

 

R1(config)#ip route 0.0.0.0 0.0.0.0 203.230.8.2

 

R3(config)#no ip route 203.230.7.0 255.255.255.0 203.230.10.1

R3(config)#no ip route 203.230.8.0 255.255.255.0 203.230.10.1

R3(config)#no ip route 203.230.9.0 255.255.255.0 203.230.10.1

 

R3(config)#ip route 0.0.0.0 0.0.0.0 203.230.10.1



R1#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 203.230.8.2 to network 0.0.0.0

203.230.7.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.7.0/24 is directly connected, GigabitEthernet0/0

L 203.230.7.1/32 is directly connected, GigabitEthernet0/0

203.230.8.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.8.0/24 is directly connected, Serial0/2/0

L 203.230.8.1/32 is directly connected, Serial0/2/0

S* 0.0.0.0/0 [1/0] via 203.230.8.2

                   AD / Metric

 

R3#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 0.0.0.0 to network 0.0.0.0

203.230.10.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.10.0/24 is directly connected, Serial0/2/1

L 203.230.10.2/32 is directly connected, Serial0/2/1

203.230.11.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.11.0/24 is directly connected, GigabitEthernet0/0

L 203.230.11.1/32 is directly connected, GigabitEthernet0/0

S* 0.0.0.0/0 is directly connected, Serial0/2/1

 

DCE(Data Communication Equipment)

 - Serial 통신 구간에서 Clock을 제공하는 장비

 

DTE(Data Terminal Equipment)

 - Serial 통신 구간에서 Clock을 제공받는 장비

 

1. Interface에 IP 주소 할당

 

Router(config)#hostname R1

R1(config)#interface gi0/0

R1(config-if)#ip address 203.230.7.1 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit

 

[참고] Serial Interface 설정

R1(config)# interface s0/2/0

R1(config-if)# ip address 203.230.7.1 255.255.255.0

R1(config-if)# clock rate CLOCK_RATE

    - Router의 Serial Interface가 DCE인 경우에만

R1(config-if)# no shutdown

R1(config-if)# exit

 

R1(config)# interface s0/2/0

R1(config-if)# ip address 203.230.7.1 255.255.255.0

R1(config-if)# clock rate 64000

R1(config-if)# no shutdown

R1(config-if)# exit

 

Router(config)#hostname R2

R2(config)#interface gi0/0

R2(config-if)#ip address 203.230.9.1 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#

R2(config)#interface s0/2/1

R2(config-if)#ip address 203.230.8.2 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#

R2(config)#interface s0/2/0

R2(config-if)#ip address 203.230.10.1 255.255.255.0

R2(config-if)#clock rate 64000

R2(config-if)#no shutdown

R2(config-if)#exit

 

Router(config)#hostname R3

R3(config)#interface gi0/0

R3(config-if)#ip address 203.230.11.1 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit

 

R3(config)#interface s0/2/1

R3(config-if)#ip address 203.230.10.2 255.255.255.0

R3(config-if)#no shutdown

 

2. Static Routing 설정

 

R1(config)#ip route 203.230.9.0 255.255.255.0 203.230.8.2

R1(config)#ip route 203.230.10.0 255.255.255.0 203.230.8.2

R1(config)#ip route 203.230.11.0 255.255.255.0 203.230.8.2

 

R2(config)#ip route 203.230.7.0 255.255.255.0 203.230.8.1

R2(config)#ip route 203.230.11.0 255.255.255.0 203.230.10.2

R3(config)#ip route 203.230.7.0 255.255.255.0 203.230.10.1

R3(config)#ip route 203.230.8.0 255.255.255.0 203.230.10.1

R3(config)#ip route 203.230.9.0 255.255.255.0 203.230.10.1

 

3. Routing Table 확인

 

Default Routing

 - Routing Table에서 목적지에 대한 경로를 비교하는 기본 원칙은 Longest Prefix Match

 - Stub Network의 경우 접근하고자 하는 모든 외부 네트워크에 대한 Routing Table 구성은 현실적으로 어려움.

 - 다른 모든 Routing 경로에 해당하지 않는 경우 패킷을 전달하는 경로를 Default Routing이라고 함.

 

 Router(config)# ip route 0.0.0.0 0.0.0.0  NEXT_HOP_IP

 Router(config)# ip route 0.0.0.0 0.0.0.0  INTERFACE

 

Default Routing으로 변경

R1(config)#no ip route 203.230.9.0 255.255.255.0 203.230.8.2

R1(config)#no ip route 203.230.10.0 255.255.255.0 203.230.8.2

R1(config)#no ip route 203.230.11.0 255.255.255.0 203.230.8.2

 

R1(config)#ip route 0.0.0.0 0.0.0.0 203.230.8.2

 

R3(config)#no ip route 203.230.7.0 255.255.255.0 203.230.10.1

R3(config)#no ip route 203.230.8.0 255.255.255.0 203.230.10.1

R3(config)#no ip route 203.230.9.0 255.255.255.0 203.230.10.1

 

R3(config)#ip route 0.0.0.0 0.0.0.0 203.230.10.1

 

R1#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 203.230.8.2 to network 0.0.0.0

203.230.7.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.7.0/24 is directly connected, GigabitEthernet0/0

L 203.230.7.1/32 is directly connected, GigabitEthernet0/0

203.230.8.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.8.0/24 is directly connected, Serial0/2/0

L 203.230.8.1/32 is directly connected, Serial0/2/0

S* 0.0.0.0/0 [1/0] via 203.230.8.2

                   AD / Metric

 

R3#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 0.0.0.0 to network 0.0.0.0

203.230.10.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.10.0/24 is directly connected, Serial0/2/1

L 203.230.10.2/32 is directly connected, Serial0/2/1

203.230.11.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.11.0/24 is directly connected, GigabitEthernet0/0

L 203.230.11.1/32 is directly connected, GigabitEthernet0/0

S* 0.0.0.0/0 is directly connected, Serial0/2/1


Distance Vector 실습 - RIP


 

RIP Routing Protocol 구성 단계

1. Interface에 IP Address 할당

R1(config)#interface gi0/0

R1(config-if)#ip address 203.230.7.1 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit

R1(config)#interface s0/2/0

R1(config-if)#ip address 203.230.10.2 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit

R1(config)#interface s0/2/1

R1(config-if)#ip address 203.230.11.2 255.255.255.0

R1(config-if)#clock rate 72000

R1(config-if)#no shutdown

R1(config-if)#exit

R1(config)#exit

 

R2(config)#interface gi0/0

R2(config-if)#ip address 203.230.9.1 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#interface s0/2/0

R2(config-if)#ip address 203.230.10.1 255.255.255.0

R2(config-if)#clock rate 72000

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#interface s0/2/1

R2(config-if)#ip address 203.230.12.1 255.255.255.0

R2(config-if)#clock rate 72000

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#exit

 

R3(config)#interface gi0/0

R3(config-if)#ip address 203.230.8.1 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit

R3(config)#interface s0/2/0

R3(config-if)#ip address 203.230.11.1 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit

R3(config)#interface s0/2/1

R3(config-if)#ip address 203.230.12.2 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit



2. RIP Routing을 구성할 Router가 관리하는 모든 네트워크를 선언

Router(config)# router rip

Router(config-router)# network  NETWORK

Router(config-router)# network  NETWORK

Router(config-router)# exit

 

R1(config)#router rip

R1(config-router)#network 203.230.7.0

R1(config-router)#network 203.230.10.0

R1(config-router)#network 203.230.11.0

R1(config-router)#exit

 

R2(config)#router rip

R2(config-router)#network 203.230.9.0

R2(config-router)#network 203.230.10.0

R2(config-router)#network 203.230.12.0

R2(config-router)#end

 

R3(config)#router rip

R3(config-router)#network 203.230.8.0

R3(config-router)#network 203.230.11.0

R3(config-router)#network 203.230.12.0

R3(config-router)#end

 

3. Routing Table 확인

R1#show ip route

Gateway of last resort is not set

203.230.7.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.7.0/24 is directly connected, GigabitEthernet0/0

L 203.230.7.1/32 is directly connected, GigabitEthernet0/0

R 203.230.8.0/24 [120/1] via 203.230.11.1, 00:00:16, Serial0/2/1

R 203.230.9.0/24 [120/1] via 203.230.10.1, 00:00:26, Serial0/2/0

203.230.10.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.10.0/24 is directly connected, Serial0/2/0

L 203.230.10.2/32 is directly connected, Serial0/2/0

203.230.11.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.11.0/24 is directly connected, Serial0/2/1

L 203.230.11.2/32 is directly connected, Serial0/2/1

R 203.230.12.0/24 [120/1] via 203.230.10.1, 00:00:26, Serial0/2/0

[120/1] via 203.230.11.1, 00:00:16, Serial0/2/1

 

R2# show ip route

Gateway of last resort is not set

R 203.230.7.0/24 [120/1] via 203.230.10.2, 00:00:08, Serial0/2/0

R 203.230.8.0/24 [120/1] via 203.230.12.2, 00:00:00, Serial0/2/1

203.230.9.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.9.0/24 is directly connected, GigabitEthernet0/0

L 203.230.9.1/32 is directly connected, GigabitEthernet0/0

203.230.10.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.10.0/24 is directly connected, Serial0/2/0

L 203.230.10.1/32 is directly connected, Serial0/2/0

R 203.230.11.0/24 [120/1] via 203.230.10.2, 00:00:08, Serial0/2/0

[120/1] via 203.230.12.2, 00:00:00, Serial0/2/1

203.230.12.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.12.0/24 is directly connected, Serial0/2/1

L 203.230.12.1/32 is directly connected, Serial0/2/1

 

R3# show ip route

Gateway of last resort is not set

R 203.230.7.0/24 [120/1] via 203.230.11.2, 00:00:18, Serial0/2/0

203.230.8.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.8.0/24 is directly connected, GigabitEthernet0/0

L 203.230.8.1/32 is directly connected, GigabitEthernet0/0

R 203.230.9.0/24 [120/1] via 203.230.12.1, 00:00:16, Serial0/2/1

R 203.230.10.0/24 [120/1] via 203.230.11.2, 00:00:18, Serial0/2/0

[120/1] via 203.230.12.1, 00:00:16, Serial0/2/1

203.230.11.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.11.0/24 is directly connected, Serial0/2/0

L 203.230.11.1/32 is directly connected, Serial0/2/0

203.230.12.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.12.0/24 is directly connected, Serial0/2/1

L 203.230.12.2/32 is directly connected, Serial0/2/1



RIP은 기본적으로 RIPv1으로 동작하며 Classless Routing이 필요한 경우 RIPv2로 구성해야 함.

 추가 명령어

   (config-router)# version 2

   (config-router)# no auto-summary

 

Link State Routing Protocol - OSPF

 

OSPF Routing Protocol 구성 단계

1. Interface에 IP Address 할당

 (Router ID 설정을 위한 Loopback 0 Interface 설정)

R1(config)#interface loopback 0

R1(config-if)#ip address 1.1.1.1 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit



R1(config)#interface gi0/0

R1(config-if)#ip address 203.230.7.1 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit

R1(config)#interface s0/2/0

R1(config-if)#ip address 203.230.10.2 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit

R1(config)#interface s0/2/1

R1(config-if)#ip address 203.230.11.2 255.255.255.0

R1(config-if)#clock rate 72000

R1(config-if)#no shutdown

R1(config-if)#exit

R1(config)#exit

 

 (Router ID 설정을 위한 Loopback 0 Interface 설정)

R2(config)#interface loopback 0

R2(config-if)#ip address 2.2.2.2 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

 

R2(config)#interface gi0/0

R2(config-if)#ip address 203.230.9.1 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#interface s0/2/0

R2(config-if)#ip address 203.230.10.1 255.255.255.0

R2(config-if)#clock rate 72000

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#interface s0/2/1

R2(config-if)#ip address 203.230.12.1 255.255.255.0

R2(config-if)#clock rate 72000

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#exit

 

(Router ID 설정을 위한 Loopback 0 Interface 설정)

R3(config)#interface loopback 0

R3(config-if)#ip address 3.3.3.3 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit

 

R3(config)#interface gi0/0

R3(config-if)#ip address 203.230.8.1 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit

R3(config)#interface s0/2/0

R3(config-if)#ip address 203.230.11.1 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit

R3(config)#interface s0/2/1

R3(config-if)#ip address 203.230.12.2 255.255.255.0

R3(config-if)#no shutdown

R3(config-if)#exit




2. OSPF Routing을 구성할 Router가 관리하는 모든 네트워크를 선언

Router(config)# router ospf  PROCESS_ID

Router(config-router)# router-id ROUTER_ID_IP_주소

Router(config-router)# network  NETWORK  WILDCARD_MASK  area   AREA_NUM

Router(config-router)# network  NETWORK  WILDCARD_MASK  area   AREA_NUM

Router(config-router)# exit

 

R1(config)#router ospf  1

R1(config-router)#router-id 1.1.1.1

R1(config-router)#network 203.230.7.0 0.0.0.255 area 0

R1(config-router)#network 203.230.10.0 0.0.0.255 area 0

R1(config-router)#network 203.230.11.0 0.0.0.255 area 0

R1(config-router)#exit

 

R2(config)#router ospf  1

R2(config-router)#router-id 2.2.2.2

R2(config-router)#network 203.230.9.0 0.0.0.255 area 0

R2(config-router)#network 203.230.10.0 0.0.0.255 area 0

R2(config-router)#network 203.230.12.0 0.0.0.255 area 0

R2(config-router)#end

 

R3(config)# router ospf  1

R3(config-router)#router-id 3.3.3.3

R3(config-router)#network 203.230.8.0 0.0.0.255 area 0

R3(config-router)#network 203.230.11.0 0.0.0.255 area 0

R3(config-router)#network 203.230.12.0 0.0.0.255 area 0

R3(config-router)#end



3. Routing Table 확인

R1#show ip route

Gateway of last resort is not set

1.0.0.0/8 is variably subnetted, 2 subnets, 2 masks

C 1.1.1.0/24 is directly connected, Loopback0

L 1.1.1.1/32 is directly connected, Loopback0

203.230.7.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.7.0/24 is directly connected, GigabitEthernet0/0

L 203.230.7.1/32 is directly connected, GigabitEthernet0/0

O 203.230.8.0/24 [110/65] via 203.230.11.1, 00:02:09, Serial0/2/1

O 203.230.9.0/24 [110/65] via 203.230.10.1, 00:03:08, Serial0/2/0

203.230.10.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.10.0/24 is directly connected, Serial0/2/0

L 203.230.10.2/32 is directly connected, Serial0/2/0

203.230.11.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.11.0/24 is directly connected, Serial0/2/1

L 203.230.11.2/32 is directly connected, Serial0/2/1

O 203.230.12.0/24 [110/128] via 203.230.10.1, 00:01:47, Serial0/2/0

[110/128] via 203.230.11.1, 00:01:47, Serial0/2/1




R2# show ip route

Gateway of last resort is not set

2.0.0.0/8 is variably subnetted, 2 subnets, 2 masks

C 2.2.2.0/24 is directly connected, Loopback0

L 2.2.2.2/32 is directly connected, Loopback0

O 203.230.7.0/24 [110/65] via 203.230.10.2, 00:03:23, Serial0/2/0

O 203.230.8.0/24 [110/65] via 203.230.12.2, 00:02:07, Serial0/2/1

203.230.9.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.9.0/24 is directly connected, GigabitEthernet0/0

L 203.230.9.1/32 is directly connected, GigabitEthernet0/0

203.230.10.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.10.0/24 is directly connected, Serial0/2/0

L 203.230.10.1/32 is directly connected, Serial0/2/0

O 203.230.11.0/24 [110/128] via 203.230.10.2, 00:02:07, Serial0/2/0

[110/128] via 203.230.12.2, 00:02:07, Serial0/2/1

203.230.12.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.12.0/24 is directly connected, Serial0/2/1

L 203.230.12.1/32 is directly connected, Serial0/2/1




R3# show ip route

Gateway of last resort is not set

3.0.0.0/8 is variably subnetted, 2 subnets, 2 masks

C 3.3.3.0/24 is directly connected, Loopback0

L 3.3.3.3/32 is directly connected, Loopback0

O 203.230.7.0/24 [110/65] via 203.230.11.2, 00:02:17, Serial0/2/0

203.230.8.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.8.0/24 is directly connected, GigabitEthernet0/0

L 203.230.8.1/32 is directly connected, GigabitEthernet0/0

O 203.230.9.0/24 [110/65] via 203.230.12.1, 00:01:58, Serial0/2/1

O 203.230.10.0/24 [110/128] via 203.230.11.2, 00:01:58, Serial0/2/0

[110/128] via 203.230.12.1, 00:01:58, Serial0/2/1

203.230.11.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.11.0/24 is directly connected, Serial0/2/0

L 203.230.11.1/32 is directly connected, Serial0/2/0

203.230.12.0/24 is variably subnetted, 2 subnets, 2 masks

C 203.230.12.0/24 is directly connected, Serial0/2/1

L 203.230.12.2/32 is directly connected, Serial0/2/1

 

Etherchannel 구성 방법

Switch(config) # interface range FastEthernet 0/X-FastEthernet0/Y

Switch(config-if-range) # channel-group  GROUP_NUM  mode  MODE

Switch(config-if-range) # channel-protocol  PROTOCOL

Switch(config-if-range) # exit

 

Etherchannel 구성 Protocol 및 모드

PAgP

 - auto : Enable PAgP if a PAgP Device is detected

              - 소극적 대기

 - desirable : Enable PAgP unconditionally

                    - PAgP 구성에 대해 적극적 협상

 

LACP

 - active : Enable LACP unconditionally

                - LACP 구성에 대해 적극적 협상

 - passive : Enable LACP only if a LACP Device is detected

                  - 소극적 대기



Etherchannel 구성 실습1

 

Switch>enable

Switch#configure terminal

Switch(config)#hostname DSW11

 

DSW11(config)#interface range fa0/21-fa0/24

DSW11(config-if-range)#channel-group 1 mode active

DSW11(config-if-range)#switchport mode access

DSW11(config-if-range)#switchport access vlan 1

DSW11(config-if-range)#exit



Switch>enable

Switch#configure terminal

Switch(config)#hostname CORE11

 

CORE11(config)#interface range fa0/21-fa0/24

CORE11(config-if-range)#channel-protocol lacp

CORE11(config-if-range)#channel-group 1 mode active

CORE11(config-if-range)#switchport mode access

CORE11(config-if-range)#switchport access vlan 1

CORE11(config-if-range)#exit



Switch>enable

Switch#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Switch(config)#hostname DSW12

 

DSW12(config)#interface range fa0/17-fa0/20

DSW12(config-if-range)#channel-group 2 mode active

DSW12(config-if-range)#switchport trunk encapsulation dot1q

DSW12(config-if-range)#switchport mode trunk

DSW12(config-if-range)#exit



CORE11(config)#interface range fa0/17-fa0/20

CORE11(config-if-range)#channel-protocol lacp

CORE11(config-if-range)#channel-group 2 mode active

CORE11(config-if-range)#switchport trunk encapsulation dot1q

CORE11(config-if-range)#switchport mode trunk

CORE11(config-if-range)#exit



Switch>enable

Switch#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Switch(config)#hostname DSW13

 

DSW13(config)#interface range fa0/13-fa0/16

DSW13(config-if-range)#no switchport

DSW13(config-if-range)#no ip address

DSW13(config-if-range)#duplex auto

DSW13(config-if-range)#speed auto

DSW13(config-if-range)#channel-group 3 mode active

DSW13(config-if-range)#exit

 

DSW13(config)#interface Port-channel 3

DSW13(config-if)#no switchport

DSW13(config-if)#ip address 192.168.3.2 255.255.255.0

DSW13(config-if)#exit



CORE11(config)#interface range fa0/13-fa0/16

CORE11(config-if-range)#no switchport

CORE11(config-if-range)#no ip address

CORE11(config-if-range)#duplex auto

CORE11(config-if-range)#speed auto

CORE11(config-if-range)#channel-group 3 mode active

CORE11(config-if-range)#exit

 

CORE11(config)#interface Port-channel 3

CORE11(config-if)#no switchport

CORE11(config-if)#ip address 192.168.3.1 255.255.255.0

CORE11(config-if)#exit

 

Switch>enable

Switch#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Switch(config)#hostname DSW14

 

DSW14(config)#interface range fa0/9-fa0/12

DSW14(config-if-range)#channel-group 4 mode active

DSW14(config-if-range)#switchport mode access

DSW14(config-if-range)#switchport access vlan 1

DSW14(config-if-range)#exit

 

DSW14(config)#interface vlan 1

DSW14(config-if)#ip address 192.168.4.2 255.255.255.0

DSW14(config-if)#no shutdown

DSW14(config-if)#exit

 

CORE11(config)#interface range fa0/9-fa0/12

CORE11(config-if-range)#channel-group 4 mode active

CORE11(config-if-range)#switchport mode access

CORE11(config-if-range)#switchport access vlan 1

CORE11(config-if-range)#exit

 

CORE11(config)#interface vlan 1

CORE11(config-if)#ip address 192.168.4.1 255.255.255.0

CORE11(config-if)#no shutdown

CORE11(config-if)#exit

 

Etherchannel 구성 확인

각 Switch에서 다음 명령어 실행

 SW#show etherchannel summary

 

게이트웨이 이중화

FHRP(First Hop Redundancy Protocol)

 - 2개 이상의 Gateway가 가상의 IP 주소로 하나의 장비처럼 동작하도록 하는 프로토콜

 

FHRP 프로토콜의 종류

 - HSRP(Hot Standby Router Protocol) : Cisco에서 만든 게이트웨이 이중화 프로토콜

 - VRRP(Virtual Router Redundancy Protocol) : IEEE 표준 게이트웨이 이중화 프로토콜

 - GLBP(Gateway Load Balancing Protocol) : 백업 게이트웨이 구성이 아닌 게이트웨이 로드밸런싱 프로토콜

 

게이트웨이 이중화 프로토콜 구성 실습

HSRP 

1. Router의 Interface에 IP 주소 할당

1-1. Routing 구성

2. HSRP 구성

Router(config)# interface INTERFACE

Router(config-if)# standby ID ip X.X.X.X

Router(config-if)# standby ID priority PRIORITY

Router(config-if)# standby ID preempt

Router(config-if)# standby ID track EXTERNAL_INTERFACE


R1(config)#interface fa0/0

R1(config-if)#standby 1 ip 192.168.1.1

R1(config-if)#standby 1 priority 105

R1(config-if)#standby 1 preempt

R1(config-if)#standby 1 track fa0/1

 

R2(config)#interface fa0/0

R2(config-if)#standby 1 ip 192.168.1.1

R2(config-if)#standby 1 priority 100

R2(config-if)#standby 1 preempt

R2(config-if)#standby 1 track fa0/1

R2(config-if)#exit

 

R1(config)#ip route 192.168.3.0 255.255.255.0 192.168.2.1

R2(config)#ip route 192.168.3.0 255.255.255.0 192.168.2.1

 

R0(config)#ip route 192.168.1.0 255.255.255.0 192.168.2.2

R0(config)#ip route 192.168.1.0 255.255.255.0 192.168.2.3

 

Router>enable

Router#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#hostname R1

R1(config)#interface fa0/0

R1(config-if)#ip address 192.168.1.2 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit

R1(config)#

R1(config)#interface fa0/1

R1(config-if)#ip address 192.168.2.2 255.255.255.0

R1(config-if)#no shutdown

R1(config-if)#exit

 

Router>enable

Router#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#hostname R2

R2(config)#interface fa0/0

R2(config-if)#ip address 192.168.1.3 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

R2(config)#interface fa0/1

R2(config-if)#ip address 192.168.2.3 255.255.255.0

R2(config-if)#no shutdown

R2(config-if)#exit

 

Router>enable

Router#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#hostname R0

R0(config)#interface fa0/0

R0(config-if)#ip address 192.168.3.1 255.255.255.0

R0(config-if)#no shutdown

R0(config-if)#exit

R0(config)#interface fa0/1

R0(config-if)#ip address 192.168.2.1 255.255.255.0

R0(config-if)#no shutdown

R0(config-if)#exit

 

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