Configuration of the DHCP service

I. Introduction to DHCP

1. Package: DHCP

2. Service Name: DHCPD (main program), Dhcrelay (relay service)

3, Port: UDP 68 UDP

4. Configuration file:

/ETC/DHCP/DHCPD.CONF Master configuration file

/etc/sysconfig/dhcrelay Relay configuration file

/usr/share/doc/dhcp*/dhcpd.conf.sample Master Profile Template

5. Common Configuration options:

Ddns-update-style Interim; Set DHCP interactive update mode

Ignore client-updates; Ignore client Updates

Subnet 192.168.12.0 netmask 255.255.255.0 {//Set subnet declaration

#---Default gateway

Option routers 192.168.12.1; Set the client default gateway

Option Subnet-mask 255.255.255.0; Setting the client subnet mask

Option Nis-domain "Ixdba.net"; Setting up NIS domains

Option Domain-name "Ixdba.net"; Set the DNS domain

Option Domain-name-servers 192.168.12.1; Set the DNS server address

Option time-offset-18000; # Eastern Standard Time//Set timing deviation

# option Ntp-servers 192.168.12.1; //Set time server

# option Netbios-name-servers 192.168.12.1; Set the NetBIOS server address

#---Selects point-to-point node (default is hybrid). Don ' t change this unless

#--You understand Netbios very well

# option Netbios-node-type 2;

Range DYNAMIC-BOOTP 192.168.12.128 192.168.12.254; Set up an address pool

Default-lease-time 21600; Set the default lease period in seconds

Max-lease-time 43200; Set the maximum client lease period in seconds

# We want the nameserver to appear at a fixed address

Host NS {//set reserved address

Server-name Marvin.    redhat.com; Server name for Assigned address

Hardware Ethernet 12:34:56:78:AB:CD; Mac of the machine that was reserved for the address

Fixed-address 207.175.42.254; Assigned IP Address

}

}

Second, the experimental process:

A) build a DHCP server:

Server-side:

1. Yum-y Install DHCP

2, since the DHCP installation is complete when there is no configuration file, you must copy from the template file a copy

Cp/usr/share/doc/dhcp*/dhcpd.conf.sample/etc/dhcp/dhcpd.conf

3, vim/etc/dhcp/dhcpd.conf Delete redundant configuration, keep a subnet area

Subnet 192.168.1.0 netmask 255.255.255.0 {

Option routers 192.168.1.2;

Option Subnet-mask 255.255.255.0;

option domain-name-servers 192.168.1.2;

Range 192.168.1.10 192.168.1.100;

Default-lease-time 21600;

Max-lease-time 23200;

}

4, Service dhcpd restart

Client:

1, the client's network card to obtain the IP mode is set to automatically get

Vim/etc/sysconfig/network-scripts/ifcfg-eth0

Device=eth0

Onboot=yes

Bootproto=dhcp

2. Restart the Network Service

Service Network restart

II) build DHCP Relay service:

Server-side:

1. Yum-y Install DHCP

2, cp/usr/share/doc/dhcp*/dhcpd.conf.sample/etc/dhcp/dhcpd.conf

3, vim/etc/dhcp/dhcpd.conf

Subnet 192.168.1.0 netmask 255.255.255.0 {

Option routers 192.168.1.2;

Option Subnet-mask 255.255.255.0;

option domain-name-servers 192.168.1.2;

Range 192.168.1.10 192.168.1.100;

Default-lease-time 21600;

Max-lease-time 23200;

}

Subnet 200.200.200.0 netmask 255.255.255.0 {

Option routers 200.200.200.1;

Option Subnet-mask 255.255.255.0;

option Domain-name-servers 200.200.200.1;

Range 200.200.200.10 200.200.200.100;

Default-lease-time 21600;

Max-lease-time 23200;

}

4, Service dhcpd restart

5. Add a gateway Record

Route add default GW 192.168.1.2

Relay side:

1. Yum-y Install DHCP

2. Set the kernel parameter configuration file to support IP forwarding

Vim/etc/sysctl.conf

Ip.net.ipv4_forward 1

3. Load configuration file

Sysctl-p

4. Configure the Relay configuration file

Vim/etc/sysconfig/dhcrelay

INTERFACE = "Eth0 eth1"

DHCPServer = "192.168.1.1"

5. Turn on the relay service

Service Dhcrelay Start

Client:

1, the client's network card to obtain the IP mode is set to automatically get

Vim/etc/sysconfig/network-scripts/ifcfg-eth0

Device=eth0

Onboot=yes

Bootproto=dhcp

2. Restart the Network Service

Service Network restart

Configuration of the DHCP service