Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Programming
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Databases
Mail Systems
openSolaris
Eclipse Documentation
Techotopia.com
Virtuatopia.com
Answertopia.com

How To Guides
Virtualization
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Windows
Problem Solutions
Privacy Policy

  




 

 

Red Hat Enterprise Linux 9 Essentials Book now available.

Purchase a copy of Red Hat Enterprise Linux 9 (RHEL 9) Essentials

Red Hat Enterprise Linux 9 Essentials Print and eBook (PDF) editions contain 34 chapters and 298 pages

Preview Book

20.3. Configuring a DHCP Client

The first step for configuring a DHCP client is to make sure the kernel recognizes the network interface card. Most cards are recognized during the installation process and the system is configured to use the correct kernel module for the card. If a card is added after installation, Kudzu [9] will recognize it and prompt you for the proper kernel module (Be sure to check the Hardware Compatibility List at https://hardware.redhat.com/hcl/). If either the installation program or kudzu does not recognize the network card, you can load the correct kernel module (refer to Chapter 40, General Parameters and Modules for details).

To configure a DHCP client manually, modify the /etc/sysconfig/network file to enable networking and the configuration file for each network device in the /etc/sysconfig/network-scripts directory. In this directory, each device should have a configuration file named ifcfg-eth0, where eth0 is the network device name.

The /etc/sysconfig/network file should contain the following line:

NETWORKING=yes

The NETWORKING variable must be set to yes if you want networking to start at boot time.

The /etc/sysconfig/network-scripts/ifcfg-eth0 file should contain the following lines:

DEVICE=eth0
BOOTPROTO=dhcp
ONBOOT=yes

A configuration file is needed for each device to be configured to use DHCP.

Other options for the network script includes:

  • DHCP_HOSTNAME — Only use this option if the DHCP server requires the client to specify a hostname before receiving an IP address. (The DHCP server daemon in Red Hat Enterprise Linux does not support this feature.)

  • PEERDNS=<answer>, where <answer> is one of the following:

    • yes — Modify /etc/resolv.conf with information from the server. If using DHCP, then yes is the default.

    • no — Do not modify /etc/resolv.conf.

  • SRCADDR=<address>, where <address> is the specified source IP address for outgoing packets.

  • USERCTL=<answer>, where <answer> is one of the following:

    • yes — Non-root users are allowed to control this device.

    • no — Non-root users are not allowed to control this device.

If you prefer using a graphical interface, refer to Chapter 14, Network Configuration for instructions on using the Network Administration Tool to configure a network interface to use DHCP.

Tip

For advanced configurations of client DHCP options such as protocol timing, lease requirements and requests, dynamic DNS support, aliases, as well as a wide variety of values to override, prepend, or append to client-side configurations, refer to the dhclient and dhclient.conf man pages.



[9] Kudzu is a hardware probing tool run at system boot time to determine what hardware has been added or removed from the system.


 
 
  Published under the terms of the Open Publication License Design by Interspire