Challenge: Does the network go down, if single element fails?
Companies can’t afford to suffer downtime on critical links that support inline appliances. Link failure propagation ensures an instant switch to the secondary link to maintain 100% uptime while networking professionals go through troubleshooting processes.
Link failure propagation (LFP) is essential for ensuring 100% network uptime when network elements fail. This feature is imperative in high availability situations with 1G copper network TAPs.
Copper gigabit networks differ because copper gigabit requires that each network port negotiate with the network TAP individually (i.e. the switch to the tap, the tap to the router).
Without LFP in a copper gigabit environment, if a network element link goes down, there’s nothing to tell the corresponding network element that there’s an issue. The functional network element continues to send packets and you start to lose visibility as a result.
LFP is designed to shut down the link attached to the TAP if one side or the other fails. In a non-HA environment, the link is turned off by the TAP and it is up to diagnostic tools to alert the maintenance folks that there is a problem.
In a HA environment, shutting down the link causes the network (not the TAP) to force a failover to the backup network so the critical link can keep flowing. This is when you can troubleshoot on the primary network to figure out what went wrong. Bear in mind that it is the critical link that we want to keep flowing. The LFP function of a TAP shuts down the critical link. That is why the LFP feature is generally used in a HA environment.
• Essential for ensuring 100% network uptime when network elements fail.
• Without LFP in Copper 1G environments, if a network element link goes down, there's nothing to tell the corresponding network element there's an issue.
• The functional element continues to send packets and you start to lose visibility. LFP ensures an instant switch to the secondary link to maintain 100% uptime.