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RouteExplorer™ Tutorial – Monitoring and Alerts

Receive alerts when service reachability changes -- Place important routingprefixes on a watch list

In the last example we showed how Route Explorer lets youmonitor or instantly see the current state of important prefix-based servicesin your multi-domain network. Route Explorer can do more. It can monitor important prefixescontinuously in the background and proactively send an alert when changesoccur.

Route Explorer supports a number of alerts on prefixes. These include:

IGP Prefix Origination Change watch list and alert – sent when a prefix is dropped or added
IGP Prefix Flap watch list and alert – sent when a prefix makes a transition from up to down or down to up, a selectable number of times in a selectable time period.
IGP Prefix Change watch list and alert – sent when a metric changes on a prefix.

As noted above, each of these prefix alerts supports a watchlist for specific prefixes. Thisallows the network engineer to place only the most important prefixes on RouteExplorer’s watch list. Weillustrate the use of one of these alerts below.

Figure 1shows Route Explorer configured to look for two up/down cycles (4 transitions)in two minutes on two prefixes and send an alert if detected.

Figure 1

The HP OpenView alarm monitor in Figure2shows examples of the traps generated.

Figure 2

Monitoring prefixes gives the earliest warning of potentialperformance problems or service outages in an IP network. This is because routing protocolsnotice changes well before SNMP polled or application monitoring systems, andin many cases before the users do. Route Explorer automates the monitoring of prefixes and presents focusedalerts to the network engineer.

HOW TO:

To enable alerts, go to the Route Explorer’s Admin web page. See the appendix to this chapter, and the Route Explorer User’s Guide.
In Route Explorer’s Admin web page, select Alerts page.
Select the appropriate alert receiving host (SNMP manager or Syslog server). If SNMP, enter the proper community string.
To see the alert, select Prefix Origination Change

Select the alert notification options (SNMP and/or Syslog)
If you wish to be alerted on ANY prefix origination change (announce/withdraw) in your network, leave the watch list empty.
If you wish to watch a particular prefix such as an anycast /32, enter it into the watchlist.

To see the alert from Route Explorer, you must also enable it in your SNMP manager. See appendix to this chapter to see and an example of how to enable Route Explorer alerts in HP OpenView.
If you selected Syslog only, ensure that the Syslog server you selected is reachable from Route Explorer. To se the laert login to the Syslog server and view the Syslog messages file
To see the Prefix Flap alert, select it in the Alerts page of the Route Explorer Admin page

Select the alert notification options (SNMP and/or Syslog)
Enter the flap frequency
If you wish to be alerted on ANY prefix flap in your network, leave the watch list empty
If you wish to watch a particular prefix for flaps, enter it into the watchlist.
To see the alert from Route Explorer, you must also enable it in your SNMP manager, or view it on your Syslog server

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