RouteExplorer™ Tutorial – Monitoring and Alerts
Get alerted on flapping links or prefixes anywhere in the network
A rapidly flapping adjacency may indicate a router interfaceabout to fail. A DNS server thatis rebooting often can impair service or be wasteful because it is notproviding the backup function it was intended for. WAN radio links may be flapping due to interference andcausing degradation of service. Route Explorer can look for these symptoms and send an alert.
With reduced staff levels hindering your ability toconstantly watch a possibly large and geographically dispersed multi-domainnetwork, many flaps may be going unnoticed. Route Explorer can be a great help.
Route Explorer supports the following alerts and associatedwatch lists that can be useful:
- IGP Adjacency Flapping – alerts when a routing adjacency is flapping. If no watch list items are configured, any flap in the network can be alerted upon.
- IGP Prefix Flapping – alerts when a prefix is flapping. If no watch list items are configured, any prefix flap in the network can be alerted upon.
- BGP Route Flapping – alerts when a BGP prefix on the watch list is flapping (Figure 1). Due to the possibly large size of the BGP route table, a watch list entry is required.
HOW TO:
- We have discussed the IGP prefix and adjacency flap alerts in previous sections.
- To enable the BGP Route Flap alert, select “Bgp Route Flap” in the Alerts page of the Route Explorer Admin page
- Select the alert notification options (SNMP and/or Syslog)
- Enter the number of flap frequency to trigger the alert.
- If you wish to watch any particular BGP routes, enter the prefix into the watch list. If the watch list is empty, any BGP route flap will trigger the alert
- 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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