Detailed explanation of DHCP distribution address of routing / layer 3 switch [Huawei ENSP]

One . Preface

DHCP： Two computers connected to the Internet communicate with each other , Must have their own IP Address , because IP Limited address resources , Broadband access operators can't allocate a fixed number of broadband subscribers IP Address , So use DHCP Method to assign temporary address to the users on the Internet .

Recently, there is a class design demand . Let's look at the demand first ：
Existing demand of a company 500 This device can be connected to the external network , The company has 5 Departments , Namely A\B\C\D\E,
Every department needs 100 device , And the second floor is required to be isolated .
As we can see above , We have finished task one ：
1. Make a reasonable plan IP（ Use private IP） With subnets .
Now let's solve demand two ：
2. It is proposed to adopt DHCP Distribution address （ expand ）
At the layer 3 switch DHCP Before sending the address , We need to have a general understanding of routing DHCP Distribution address , as follows ：

Two . route DHCP Distribution address

Take a look at the topology ：

First step , Go to the router first ：
Get into 0/0/0

int GigabitEthernet 0/0/0

Add gateway and mask

[R1-GigabitEthernet0/0/0]ip address 192.168.1.254 24

go back to R1
Create an address pool

[R1]ip pool PC

Input gateway

[R1-ip-pool-PC]gateway-list 192.168.1.254

Input network segment

[R1-ip-pool-PC]network 192.168.1.0 mask 24

Return to R1
Turn on DHCP

[R1]dhcp enable 

Get into 0/0/0

[R1]int GigabitEthernet 0/0/0

Turn on global overall situation

[R1-GigabitEthernet0/0/0]dhcp select global 

testing ：

ipconfig

3、 ... and . Switch DHCP Distribution address ( Lord ）

3.1 The detailed steps

Take a look at the topology first ：

We have done subnet division before , as follows ：

To configure DHCP Here comes the step ： high energy alert ！
Step 1 access layer ：
First configure the access layer switch LSW1~LSW5：
First configure vlan

vlan batch 10 20 30 40 50

Set the interface of the access terminal to access Pattern , release vlan10 adopt

int Eth0/0/1
port link-type access
port default vlan 10

Set other 3 Interfaces are trunk Pattern , Let go of all vlan adopt

port-group group-member Ethernet 0/0/2 to Ethernet 0/0/3
port link-type trunk
port trunk allow-pass vlan all

The above steps configure LSW1~LSW5, Be careful port default vlan 10 Switches in different access layers need to be changed

Step 1 convergence layer ：
Configure the aggregation layer switch , has SWL6 For example .
stay LSW6 Upper opening VLAN

vlan batch 10 20 30 40 50

Set interface group , Set to trunk Pattern ：

port-group group-member GigabitEthernet 0/0/1 to GigabitEthernet 0/0/9
port link-type trunk

Release all vlan：

port trunk allow-pass vlan all

Switch on DHCP

dhcp enable

Write logical interface ,ip The address is the terminal gateway address , Mask 25 position

int vlanif 10
ip address 192.168.10.126 25

Create five ip pool , And assign ip paragraph , Distribute gateway

ip pool 1
network 192.168.10.0 mask 25
gateway-list 192.168.10.126

Select the global address pool for DHCP Client side usage

int Vlan 10
dhcp select global

The terminal device is set to DHCP

Input ipconfig

DHCP Address distribution succeeded ！

3.2 Convenient command collection

Access layer switch

vlan batch 10 20 30 40 50
int Eth0/0/1
port link-type access 
port default vlan 10
port-group group-member Ethernet 0/0/2 to Ethernet 0/0/3
port link-type trunk 
port trunk allow-pass vlan all

Convergent layer switch

vlan batch 10 20 30 40 50
port-group group-member GigabitEthernet 0/0/1 to GigabitEthernet 0/0/9
port link-type trunk
port trunk allow-pass vlan all

Switch on DHCP

dhcp enable

int vlanif 10
ip address 192.168.10.126 25

int vlanif 20
ip address 192.168.10.254 25

int vlanif 30
ip address 192.168.20.126 25

int vlanif 40
ip address 192.168.20.254 25

int vlanif 50
ip address 192.168.30.126 25

Switch on DHCP
[sw1]dhcp enable

dhcp enable

Create five ip pool , And assign ip paragraph , Distribute gateway

ip pool 1
network 192.168.10.0 mask 25
gateway-list 192.168.10.126

ip pool 2
network 192.168.10.128 mask 25
gateway-list 192.168.10.254

ip pool 3
network 192.168.20.0 mask 25
gateway-list 192.168.20.126

ip pool 4
network 192.168.20.128 mask 25
gateway-list 192.168.20.254

ip pool 5
network 192.168.30.0 mask 25
gateway-list 192.168.30.126

Select the global address pool for DHCP Client side usage

int Vlan 10
dhcp select global 

int Vlan 20
dhcp select global 

int Vlan 30
dhcp select global 

int Vlan 40
dhcp select global 

int Vlan 50
dhcp select global