Managing NFS and NIS, 2nd Edition

Chapter 17. Network Performance Analysis

This chapter explores network diagnostics and partitioning schemes aimed at reducing congestion and improving the local host’s interface to the network.

Network congestion and network interfaces

A network that was designed to ensure transparent access to filesystems and to provide “plug-and-play” services for new clients is a prime candidate for regular expansion. Joining several independent networks with routers, switches, hubs, bridges, or repeaters may add to the traffic level on one or more of the networks. However, a network cannot grow indefinitely without eventually experiencing congestion problems. Therefore, don’t grow a network without planning its physical topology (cable routing and limitations) as well as its logical design. After several spurts of growth, performance on the network may suffer due to excessive loading.

The problems discussed in this section affect NIS as well as NFS service. Adding network partitioning hardware affects the transmission of broadcast packets, and poorly placed bridges, switches, or routers can create new bottlenecks in frequently used network “virtual circuits.” Throughout this chapter, the emphasis will be on planning and capacity evaluation, rather than on low-level electrical details.

Local network interface

Ethernet cabling problems, such as incorrect or poorly made Category-5 cabling, affect all of the machines on the network. Conversely, a local interface problem is visible only to the ...