理论学习

问题1:三层交换机的路由共有几种实现方式?

1) 虚拟交换接口(svi)

2) 路由接口(routed)

3) 三层聚合链路(L3 Aggregate Link) 接口

 

问题2:描述单臂路由的实现原理?

 

单臂路由是在二层交换机上进行vlan 划分的,然后通过一条中继链路连接路由器的一个接口(通常路由需要使用至少两个接口来实现路由功能,而现在只需要一个接口,就像一条胳膊在发挥作用,所以 称之为单臂路由),在路由器上通过配置子接口和802.1Q 协议封装最终实现在vlan 信息和子网一一对应,即实现vlan 间的路由功能。

 

 

问题3:SVI的含义是什么?如何实现VLAN间路由?

 

交换机虚拟接口(Switch Virtual Interface,SVI)代表一个由交换端口构成的VLAN(其实就是通常所说的VLAN接口),以便于实现系统中路由和桥接的功能。一个交换机虚拟接口对应一个VLAN,当需要路由虚拟局域网之间的流量或桥接VLAN之间不可路由的协议,以及提供IP主机到交换机的连接的时候,就需要为相应的虚拟局域网配置相应的交换机虚拟接口,其实SVI就是指通常所说的VLAN接口,只不过它是虚拟的,用于连接整个VLAN,所以通常也把这种接口称为逻辑三层接口,也是三层接口。

三层可以划分vlan给vlan设置一个地址当网关 ,实现vlan间的路由

也可以在二层创建vlan,三层通过虚拟子接口 创建单臂路由,实现vlan间的路由

问题4:路由接口和SVI接口实现路由什么不同

 

svi接口说白了就是vlan接口,在上面配上ip,然后把二层端口加入进来,以前的设备不能直接在端口 上配ip,就用svi接口方式来配ip,实现三层连接。

而路由接口,是直接在端口上设置ip来实现路由

 

5:交换机的VLAN有哪些类型?

 

1) 业务vlan

2) 互联vlan

   3)  管理vlan


工作任务描述

某公司现有两个部门,每个部门各有100台左右的计算机,所有计算机位于同一子网,现在发现整个网络的通信质量很差,请问如何进行网络改造以提高网络通信质量。

工作任务实施

网络拓扑结构设计(粘贴PT的拓扑图)

交换设置vlan的网关 给vlan配网关_交换设置vlan的网关

方案一:SW1连接A部门的计算机,SW2连接B部门计算机,两台二层交换机不做任何配置,仅用于网络接入,而这两台二层交换机上行线路分别连接到RS交换机的一个VLAN,为RS的两个VLAN配置IP地址即可实现VLAN间路由功能。这种网络的规划和配置适合于A、B两部门的计算机相对独立的连接在各自的交换机上,仅需要解决的是两个部门之间的路由问题。

        方案一配置:

 

Rs
 
RS#show run
Building configuration...
 
Current configuration : 1307 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname RS
!
!
!
ip routing
!
!
spanning-tree mode pvst
!
!
interface FastEthernet0/1
!
(省略……)
!
interface FastEthernet0/23
 switchport access vlan 2
 switchport mode access
!
interface FastEthernet0/24
 switchport access vlan 3
 switchport mode access
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan2
 ip address 192.168.1.254 255.255.255.0
!
interface Vlan3
 ip address 192.168.2.254 255.255.255.0
!
ip classless
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
!
end
 
 
 
 
 
试以及查看RS的路由
 
RS# 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
 
C    192.168.1.0/24 is directly connected, Vlan2
C    192.168.2.0/24 is directly connected, Vlan3

方案二:如果A、B部门的计算机由于地理位置的原因,分别连接在SW1和SW2交换机上,则需要将SW1和SW2的两条上行线路设置为Trunk线路,RS交换机采用VTP域的模式实现扩展VLAN的功能,然后在RS三层交换机上通过配置各个VLAN的IP地址实现两个VLAN之间的路由功能。

方案二配置:

RS
 
RS#show run
Building configuration...
 
Current configuration : 1381 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname RS
!
!
ip routing
!
!
spanning-tree mode pvst
!
!
interface FastEthernet0/1
!
(省略……)
!
interface FastEthernet0/23
 switchport access vlan 2
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface FastEthernet0/24
 switchport access vlan 3
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan2
 ip address 192.168.1.254 255.255.255.0
!
interface Vlan3
 ip address 192.168.2.254 255.255.255.0
!
ip classless
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
end
 
 
Sw1
 
 
Sw1#show run
Building configuration...
 
Current configuration : 1091 bytes
!
version 12.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Sw1
!
!
spanning-tree mode pvst
!
interface FastEthernet0/1
 switchport access vlan 2
 switchport mode access
!
interface FastEthernet0/2
 switchport access vlan 3
 switchport mode access
!
interface FastEthernet0/3
!
(省略……)
!
interface FastEthernet0/24
 switchport mode trunk
!
interface Vlan1
 no ip address
 shutdown
!
!
line con 0
!
line vty 0 4
 login
line vty 5 15
 login
!
!
end
 
 
Sw2
 
Sw2#show run
Building configuration...
 
Current configuration : 1091 bytes
!
version 12.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Sw2
!
!
spanning-tree mode pvst
!
interface FastEthernet0/1
 switchport access vlan 2
 switchport mode access
!
interface FastEthernet0/2
 switchport access vlan 3
 switchport mode access
!
interface FastEthernet0/3
!
(省略……)
!
interface FastEthernet0/24
 switchport mode trunk
!
interface Vlan1
 no ip address
 shutdown
!
!
line con 0
!
line vty 0 4
 login
line vty 5 15
 login
!
!
end
试以及查看RS的路由
 
RS#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
 
C    192.168.1.0/24 is directly connected, Vlan2
C    192.168.2.0/24 is directly connected, Vlan3
 
如果改为三层接口如何实现
RS
 
show run
Building configuration...
 
Current configuration : 1317 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname RS
!
!
ip routing
!
!
spanning-tree mode pvst
!
!
interface FastEthernet0/1
!
(省略……)
!
interface FastEthernet0/23
 no switchport
 ip address 192.168.1.254 255.255.255.0
 duplex auto
 speed auto
!
interface FastEthernet0/24
 no switchport
 ip address 192.168.2.254 255.255.255.0
 duplex auto
 speed auto
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan2
 no ip address
!
interface Vlan3
 no ip address
!
ip classless
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
end

工作扩展

扩展ACL的配置

由于购买三层交换机的投入较大,上述实验我们也可以采用一种较为省钱的方法来实现,就是采用单臂路由,这样只要加入一个路由器,就可以实现二层交换机各VLAN间的路由了。

     具体配置:

R1
 
R1#show run
Building configuration...
 
Current configuration : 594 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname R1
!
!
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
!
interface FastEthernet0/0.1
 encapsulation dot1Q 2
 ip address 192.168.1.254 255.255.255.0
!
interface FastEthernet0/0.2
 encapsulation dot1Q 3
 ip address 192.168.2.254 255.255.255.0
!
interface FastEthernet0/1
 no ip address
 duplex auto
 speed auto
 shutdown
!
ip classless
!
!
line con 0
!
line aux 0
!
line vty 0 4
 login
!
!
end
 
Switch
 
 
show run
Building configuration...
 
Current configuration : 1094 bytes
!
version 12.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Switch
!
!
spanning-tree mode pvst
!
interface FastEthernet0/1
 switchport access vlan 2
 switchport mode access
!
interface FastEthernet0/2
 switchport access vlan 3
 switchport mode access
!
interface FastEthernet0/3
!
(省略……)
!
interface FastEthernet0/24
 switchport mode trunk
!
interface Vlan1
 no ip address
 shutdown
!
!
line con 0
!
line vty 0 4
 login
line vty 5 15
 login
!
!
end

思考问题:

问题1:单臂路由和三层交换机的VLAN间路由有什么不同?

 



转载于:https://blog.51cto.com/9984466/1667526