HP Network Direr Software Products manual Configurable Discovery Options

686CHAPTER 17: USING 3COM NETWORK DIRECTOR ON A MULTI-SITE NETWORK

By changing the monitoring mode used for remote devices you can reduce the amount of monitoring traffic that will be generated on the WAN links, reducing the impact that monitoring has upon these links.

Configurable Discovery Options

In order to discover your network, 3Com Network Director performs a series of steps in order to find devices, determine their configuration and calculate how they are interconnected. Most of these steps involve generating traffic on your network. If you are discovering a remote site then this will generate traffic on the WAN links on the route to that site. This increase in utilization can increase the latency of the links and possibly even cause them to become oversubscribed.

There are various options within the Network Discovery wizard that allow you to control the discovery of your network. These include selecting the subnets and IP address ranges that you wish to discover, restricting the discovery to certain device types and configuring the number of retries and timeout periods to use. All of these options can be used to reduce the amount of traffic that a Network Discovery generates and to allow the discovery process to complete successfully even in situations where there are unreliable WAN links in the routes to the remote sites.

For more details on the discovery process, see “Discovering the Network” on page 91.

Configurable Monitor Thresholds

Service monitors, such as the IP Ping Service monitor, provide a useful indication whether devices or services are available and how quick they are to respond to certain request types. As is discussed above, if the route to a remote site passes over one or more WAN links with high latency then the remote devices at that site may naturally respond slower to requests than local devices.

By increasing the threshold for a service monitor you can increase the range of response times that 3Com Network Director considers to be normal, which will prevent 3Com Network Director from incorrectly reporting these devices as having slow response times.