Network Monitoring

John Berninger

The average system administrator's job involves more than simply installing systems and creating user accounts. Most of the time, the administrator works to ensure system availability and reliability. One method of accomplishing that is through the use of network-specific software tools. Although such tools are extremely useful to a networking administrator, they are not always useful to the UNIX administrator worried about performance, network throughput at the NIC, processor load, and other platform-specific issues.

The recognition of the interdependence between systems and the networks to which they are attached has led to the development of enterprise monitoring tools such as HP's Openview and IBM's Tivoli. These tools, because they are designed to do so much, are often difficult to install, tedious to configure, and time consuming to actually plan, configure, and implement. Such commercial tools are also relatively expensive, and thus difficult to cost-justify if management lacks the technical expertise to understand the scope of the problems addressed by the tools.

In my position, I needed an inexpensive tool that would do some basic network-availability monitoring and, just as importantly, tell me something about the servers I am responsible for administering. I also wanted a tool that I could quickly deploy to another machine or set of machines, so I would not necessarily be confronted with trans-firewall communications issues while monitoring disparate networks separated by a firewall. This article describes the tool I developed, and the rationale behind the features it provides.

Development Rationale

In my environment, I had to work within some significant development constraints.