Cisco Systems Inc. - Cisco routers for the desperate: router and switch management, the easy way

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The main goal of this book is to make you comfortable with the environment and technology found inside every Cisco router. First, you have to connect to the router and log in. You also need to examine interfaces, check the configuration, and change the system's current and startup configurations as well as run some basic troubleshooting commands.

To make the router work properly, you need a basic comprehension of the network connections most commonly found on modern TCP/IP networks. We'll briefly cover Ethernet and serial lines and give some pointers to further information. This isn't a primer on networking, but you need to understand enough theory to understand why things aren't working.

We'll then discuss the most common router usage, connecting a small network to the Internet. A step-by-step discussion of the typical configuration choices will help you preconfigure a router so that you can quickly and easily establish a new connection with a minimum of fuss. This will allow you to ask your ISP for the specific information you need, rather than their install tech telling you what you need to obediently type. To make your Internet connection work, you'll also have to configure the router's Ethernet interface, so we'll discuss that as well.

Perhaps the second most common use of a router is to connect two offices with a private leased line. This is a step up from connecting a network to an ISP, and we'll cover how to make this happen, beginning with ordering the circuit from the telephone company. Because you'll be responsible for this circuit, we'll cover troubleshooting as well.

As good as Cisco equipment is, its products require occasional software updates to solve stability and security problems. We'll take you through doing this safely and reliably, and we'll discuss recovering from the most common problems.

Whenever the office Internet connection goes down, managers all have the same question: "What would it take to get redundancy?" We'll unveil the mysteries of BGP, the Border Gateway Protocol, and show how you, as a small network provider, can use BGP to provide some measure of network redundancy. We'll also discuss the problems associated with BGP and some workarounds that can solve those problems.

Once you've mastered all of this, adding Ethernet switch expertise is easy. We'll detour into the Ethernet switching realm so that you can manage the hardware supporting your LAN as well as your WAN.

Finally, Cisco routers can take advantage of a variety of network services that you might already offer and include other interfaces to more easily fit with your network. These include such basic protocols as SSH (Secure Shell), NTP (Network Time Protocol), and SNMP (Simple Network Management Protocol). We'll briefly discuss how to configure these and more.

If you need more information, it's available elsewhere for either a small fee or at no cost.