Book Image

Linux Networking Cookbook

By : Agnello Dsouza, Gregory Boyce
5 (1)
Book Image

Linux Networking Cookbook

5 (1)
By: Agnello Dsouza, Gregory Boyce

Overview of this book

Linux can be configured as a networked workstation, a DNS server, a mail server, a firewall, a gateway router, and many other things. These are all part of administration tasks, hence network administration is one of the main tasks of Linux system administration. By knowing how to configure system network interfaces in a reliable and optimal manner, Linux administrators can deploy and configure several network services including file, web, mail, and servers while working in large enterprise environments. Starting with a simple Linux router that passes traffic between two private networks, you will see how to enable NAT on the router in order to allow Internet access from the network, and will also enable DHCP on the network to ease configuration of client systems. You will then move on to configuring your own DNS server on your local network using bind9 and tying it into your DHCP server to allow automatic configuration of local hostnames. You will then future enable your network by setting up IPv6 via tunnel providers. Moving on, we’ll configure Samba to centralize authentication for your network services; we will also configure Linux client to leverage it for authentication, and set up a RADIUS server that uses the directory server for authentication. Toward the end, you will have a network with a number of services running on it, and will implement monitoring in order to detect problems as they occur.
Table of Contents (19 chapters)
Linux Networking Cookbook
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Adding Nagios hosts


Monitoring the local system is different than monitoring remote systems. A big part of this is that while monitoring your local system, you have full access to information regarding number of processes, amount of memory, CPU usage, and so on. When you're looking at remote systems, you're limited to accessing remotely accessible information like if a remote port is listening, ping ability, and so on. If you require the ability to collect more in depth information, you'll need to configure something to make the additional information available.

How to do it…

You can configure additional hosts to be monitored by Nagios by creating additional host entry in a .cfg file within /etc/nagios3/conf.d/.

The content should be:

define host {
        use                     generic-host 
        host_name               testbox
        hostgroups              http-servers,ssh-servers
}

While multiple machines may be defined within the same .cfg file, separate files per machine may make more...