Configuring Dhcp for Linux

You can manage the configuration of the Linux DHCPD service by editing the dhcpd.conf configuration file. The dhcpd.conf is located at /etc/dhcp directory of most Linux distributions. If the DHCP is not installed on your Linux server, install the Network Infrastructure Server or similar services.

Before you start editing the dhcpd.conf file, it is recommended to back up the file. After you install the appropriate network services, you must configure the dhcpd.conf file before you start the DHCPD service.

The DHCP configuration must include the following options:

•next-server <IP address>

Indicates the IP address of the PXE server. That is, the IP address of ASM appliance vNIC that exists on the PXE network.

•filename "bootstrap.ipxe"

NOTE: For PXE service to function properly, you must specify bootstrap.ipxe for the file name.

The PXE service uses iPXE service. You must use two different bootstrap files for the PXE environment, one for the initial PXE boot, which starts up the system to the final iPXE boot file.

To run this operation, add the following code to the dhcpd.conf file:

if exists user-class and option user-class = "iPXE" { filename "bootstrap.ipxe";

} else {

filename "undionly.kpxe";

}

Secondly, add the following code to the subnet declaration within your dhcpd.conf file. This code instructs a legacy PXE server to boot to a legacy boot file, and then directs to the iPXE boot file. For more details, see the Sample DHCP Configuration

The configuration file must contain the following information:

#dhcpd.conf

#Sample configuration file for ISC dhcpd

next-server 192.168.123.21;# IP address of ASM Server default-lease-time 6000;

max-lease-time 7200; authoritative; log-facility local7;

subnet 192.168.123.0 netmask 255.255.255.0 { range 192.168.123.24 192.168.123.29; option subnet-mask 255.255.255.0; option routers 192.168.123.1;

if exists user-class and option user-class = "iPXE" { filename "bootstrap.ipxe";

} else {

filename "undionly.kpxe";

}