One 、 Static routing configuration

review
1、 Static routing

• It is manually configured by the administrator , It's one way , inflexibility

2、 Default route

• A kind of static routing , A special . It's right IP When the destination address in the packet cannot find another route that exists , The route selected by the router . All packets whose destination is not in the router's routing table will use the default routing . This route is usually connected to another router , The router also processes packets : If you know how to route this packet , Then the packet will be forwarded to a known route ; otherwise , Packets are forwarded to the default route , To reach another router . Every forwarding , Routing increases the distance of one hop .

1、 Static routing

ip route Target network （ Target network segment “ The network address of the target ") Subnet mask of the target Next hop address （ The interface of the next router IP Address ) Or send it to the local interface of the next router （ That is, the interface's own , This interface points to the next route ）

ip route 192.168.10.0 255.255.255.0 192.168.30.2

ip route 192.168.10.0 255.255.255.0 f0/1

2、 Default route

ip route 0.0.0.0 0.0.0.0 192.168.30.2

ip route 0.0.0.0 0.0.0.0 f0/1

3、 View routing entries

Cisco ：

show ip route

Comprehensive experiment ：
Experimental apparatus ： Three 2911 Router , Two sets of PC, Connect with lightning

The experimental requirements ：
requirement 1：PC0 visit PC1 Step up , Through three routers
requirement 2：PC1 visit PC0 Go down , Through two routers
1、 According to the parameters in the figure below , Set it up first PC Of IP, Here, you can set it in the graphical interface



ps： The default gateway , Also called default gateway , That is, the router and PC Connected interface IP Address . Default gateway （Default Gateway） It is a device connected between subnet and extranet , It's usually a router . When a computer sends a message , According to the destination address of the message , Determine whether the target host is in the local subnet through the subnet mask , If the target host is in the local subnet , Then you can send it directly . If the target is not in the local subnet, the information is sent to the default gateway / Router , The router forwards it to other networks , Find further target hosts .

2、 Then set up the router IP Parameters , At this time, use the command line to set



ps: Figures in the above figure and g0/0 Your address is wrong , Should be 192.168 Of , instead of 192.169 Of , Just change it yourself
3、 stay r1 Configure static routing on
It can be used show ip route See if the configuration is successful

4、 stay r0 Configure static routing on

5、 At this time, the message can be delivered PC1 了 , Now the design returns PC0 The path of . First in R2 Set the default route , Direction of transmission R1

6、 Go to ping 192.168.20.20, for the first time ping It didn't work , The second time it worked

7、 You can also use simulation mode , Graphically view the distance of the message

Two 、 Configuration on router DHCP

Purpose ： So that the client can be provided by the router DHCP The service gets IP Address
DHCP: Dynamic Host Configuration Protocol
Mainly for clients TCP/IP Parameters :IP Address 、 Subnet mask 、 gateway 、DNS Server address

1、 Ideas

• Definition DHCP Address pool
  （1） The name of the pool

r0(config)#ip dhcp pool zixin

（2） Specify the assigned network range ： Network address and subnet mask 、

r0(dhcp-config)#network 192.168.10.0 255.255.255.0

（3） Specify the default gateway

r0(dhcp-config)#default-router 192.168.10.254

（4） Appoint DNS Server address

r0(dhcp-config)#dns-server 114.114.114.114

• Specify the reserved address
  Reserved address , That is, the address taken out for standby

r0(config)#ip dhcp excluded-address 192.168.10.1 192.168.10.50

1、 As shown in the following figure , Configure the interface of the router IP

Code samples ：
Router(config)#int g0/0
Router(config-if)#ip add 10.0.0.2 255.255.255.0
Router(config-if)#no shut


2、 Configure static routing on the router
There's only one direction , Why set up static routes ？ Because although only one direction can be forwarded , But as long as the routing table has no routing information , It will not be forwarded .
First in r0 On the configuration ：r0(config)#ip route 192.168.20.0 255.255.255.0 g0/1
View after configuration ：r0#show ip route

Go again r1 On the configuration ：r1(config)#ip route 192.168.10.0 255.255.255.0 g0/0
View after configuration ：r1#show ip route

3、 In the router r0 Middle configuration DHCP
The name of the address pool ：r0(config)#ip dhcp pool zixin
Specify the assigned network range ： Network address and subnet mask ：r0(dhcp-config)#network 192.168.10.0 255.255.255.0
Specify the default gateway ：r0(dhcp-config)#default-router 192.168.10.254
Appoint DNS Server address ：r0(dhcp-config)#dns-server 114.114.114.114（ Our experiment did not dns, So casually matched ）
Specify the reserved address ：r0(config)#ip dhcp excluded-address 192.168.10.1 192.168.10.50


4、 stay PC0 Graphical page acquisition in DHCP



5、 above 3、4 The operation of r1 Once again


6、 stay PC0 in pingPC1:ping 192.168.20.101
For the first time, three did not ping success , Second full ping success

3、 ... and 、 Virtual LAN VLAN

• It is mainly used in switches
• A switch is connected to a broadcast domain by default , Because by default, all interfaces belong to the same vlan Of , Default vlan 1, So it is in the same broadcast domain

1、 Purpose

• Divide the broadcast area , Different broadcast domains cannot communicate , If you want to communicate , At this time, you need to use routing
• Enhance network security
• Divide the broadcast domain into different areas , Namely different vlan, Simplify network management
  

2、vlan The type of

• static state vlan
  Based on port partition , Need management to configure , establish vlan And add the interface to vlan
• dynamic wlan
  Less use . be based on MAC The address will automatically be the same type MAC Add the address to the same VLANT

3、 static state vlan

• vlan The scope of the （ Cisco equipment ）. If it's Huawei equipment , There will be differences .
  A total of 4096 individual vlan 0~4095
  0 ,4095 Retain
  Default vlan 1
  Ethernet vlan 2~1001
  Extended Ethernet vlan 1025~4094
• Configure static vlan
  （1） establish vlan
  Law 1 ：
  Create directly in global mode :vlan 2
  View the created in privileged mode vlan：show vlan brief
  Law two ：
  stay vlan Create in the database ：
  Enter the first ：vlan database
  after ：vlan 2
  （2） Add the interface to vlan
  You need to specify the mode of the interface
  Add a single interface ：

Switch(config)#int f0/10
Switch(config-if)#switchport mode access
Switch(config-if)#switchport access vlan 2

Multiple interfaces are added ：

 Switch(config)#int range f0/20-24
 Switch(config-if-range)#switchport mode access
Switch(config-if-range)#switchport access vlan 3

Comprehensive experiment ：
1、 Cisco builds a new one 2960 Switch , And create and view in the switch vlan


2、 A single interface is added vlan 2：

3、 Multiple interfaces are added vlan 3：

• Other configuration commands
  View specified vlan：show vlan id 2
  Delete ： Enter in global mode no vlan 2

By creating vlan, Add different hosts to the corresponding vlan after , Under the same switch , identical vlan You can communicate directly , Different vlan Unable to communicate directly