Network Troubleshooting Tools

Chapter 7. Device Monitoring with SNMP

This chapter is about monitoring devices with Simple Network Management Protocol (SNMP). It describes how SNMP can be used to retrieve information from remote systems, to monitor systems, and to alert you to problems. While other network management protocols exist, SNMP is currently the most commonly used. While SNMP has other uses, our primary focus will be on monitoring systems to ensure that they are functioning properly and to collect information when they aren’t. The material in this chapter is expanded upon in Chapter 8.

This chapter begins with a brief review of SNMP. This description is somewhat informal but should serve to convey enough of the basic ideas to get you started if you are unfamiliar with SNMP. If you are already familiar with the basic concepts and vocabulary, you can safely skip over this section. Next I describe NET SNMP—a wonderful tool for learning about SNMP that can be used for many simple tasks. Network monitoring using tkined is next, followed by a few pointers to tools for Microsoft Windows.

Overview of SNMP

SNMP is a management protocol allowing a management program to communicate, configure, or control remote devices that have embedded SNMP agents. The basic idea behind SNMP is to have a program or agent running on the remote system that you can communicate with over the network. This agent then can monitor systems and collect information. Software on a management station sends messages to the remote agent ...