Forwarding

Floating static route

Also called backup route, floating static

A backup static route with a higher administrative distance, used only when the main route is gone.

ip route 10.0.2.0/24 10.0.13.3 200 waits behind a route to the same prefix with a lower distance (a static at 1, or OSPF at 110), and is installed when that route is withdrawn: its card goes down, or the protocol loses it. A static route cannot see a silent failure on a link that stays up; BFD or IP SLA tracking can.

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