CentOS 6 Linux Server Cookbook: An all-in-one guide to installing, configuring, and running a Centos 6 server. Ideal for newbies and old-hands alike, this practical tutorial ensures you get the best from this popular, enterprise-class free server solution.

This chapter is a collection of recipes that covers the practice of priming your server by changing the time zone and updating the hardware clock; synchronizing the system clock with NTP; setting a static IP address; binding multiple IP addresses to a single Ethernet device; bonding two Ethernet devices to increase bandwidth and improve performance; changing the hostname and resolving a fully qualified domain name; switching SELinux off; and disabling the IPv6 module.

In this recipe we will introduce the concept of TZDATA in order that we can learn how to change a server's time zone and update the hardware clock.

Over the lifetime of your server, the need to change the time and date for one or more users may not happen very often but when it does the process of managing this modification can seem to be quite complicated. You may want to make this change for any number of reasons, you can even use this approach to implement an independent time zone solution for different users, but regardless as to the reason why, it is the purpose of this recipe to illustrate a series of best practices that can be applied to your server and provide you with the solution you need.

In this recipe, we will learn how to synchronize the system clock with an external time server using NTP.

Time remains an essential tool for your server because every aspect of managing, securing, running, and debugging a network involves determining when events happen or are about to take place. From the need to time stamp documents, e-mails, logfiles, or by simply interacting with shared devices and services, everything on your server is dependent on maintaining an accurate system clock and it is the purpose of this recipe to show you how to achieve this with the Network Time Protocol (NTP).

In this recipe we will learn how to configure a static IP address for a new or existing CentOS server.

While a dynamically assigned IP address or DHCP reservation may be fine for most desktop and laptop users, if you are setting up a server it is often the case that you will require a static IP address. From web pages to e-mail, databases to file sharing, a static IP address will become a permanent location from which your server will deliver a range of applications and services, and it is the intention of this recipe to show you how easily it can be achieved.

In this recipe we will learn how to bind multiple IP addresses to a single Ethernet device in order to provide greater networking functionality to a new or existing CentOS server.

There are many advantages to using a static IP address, but combining this with the ability to use more than one will present you with a new range of configuration options. Clearly, the benefit of circumventing the need to purchase and install multiple Ethernet devices is obvious, but this approach will not only enable you to run multiple servers and websites, it can also enable you to create a private LAN using a local IP and have the alias hold your Internet IP. So with that in mind, it is the purpose of this recipe to show you how easily an IP-rich server can be achieved.

In this recipe we will learn how to combine the features of multiple network interfaces as a single device in an arrangement known as channel bonding with the intention of improving the overall performance of your server.

If your server has more than one Ethernet device, the process of channel bonding allows you to bind these interfaces together into a single channel in order to increase bandwidth and provide redundancy. It may sound complicated and finding the best settings will require some experimentation on your behalf or the support of specific network-based hardware, but it is the purpose of this recipe to provide a suitable starting point that enables you to take control and discover a network configuration that suits you best.

In this recipe we will learn how to change the hostname and resolve the Fully Qualified Domain Name (FQDN) of your server.

The process of setting the hostname is typically associated with the installation process but on many occasions there comes a time when the name used is either incorrect for a technical reason or you just don't like it any more. For some people the name of the server lacks importance, but for many others, a good server demands a good name and so it is the purpose of this recipe is to show you how quickly the hostname can be changed with the intention to revise and resolve the resulting fully qualified domain name.

In this recipe we will consider the need to switch Security-Enhanced Linux (SELinux) off in order to ease the process of installing packages and managing your server.

Security-Enhanced Linux is a very robust security mechanism that is enabled by default. It is designed to improve the security of your server but on occasion it has been the case that you have been required to disable it in order to install a new package or to speed up the process of server management. This is not a decision you will make in haste, but it is the purpose of this recipe to show you how this can be achieved and this solution can be seen as both, temporary or permanent, depending on your needs.

In this recipe we will consider the need to disable the IPv6 module on a CentOS server.

IPv6 was designed to solve the problems of IPv4, but it is an accepted fact that not everyone uses it and not all hardware supports it. The deployment of IPv6 is accelerating but for this reason it is also a possibility that some environments will expect that IPv6 has been disabled on the server. This is certainly not unusual, and in these circumstances, you may find that disabling IPv6 will not only speed up networking, but it will also serve to reduce an administrative overhead and improve your current level of security.