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13-2
Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x
OL-20002-02
Chapter 13 Configuring Static Routing
Information About Static Routing
• Directly Connected Static Routes, page 13-2
• Fully Specified Static Routes, page 13-2
• Floating Static Routes, page 13-2
• Remote Next Hops for Static Routes, page 13-3
Administrative Distance
An administrative distance is the metric used by routers to choose the best path when there are two or
more routes to the same destination from two different routing protocols. An administrative distance
guides the selection of one routing protocol (or static route) over another, when more than one protocol
adds the same route to the unicast routing table. Each routing protocol is prioritized in order of most to
least reliable using an administrative distance value.
Static routes have a default administrative distance of 1. A router prefers a static route to a dynamic route
because the router considers a route with a low number to be the shortest. If you want a dynamic route
to override a static route, you can specify an administrative distance for the static route. For example, if
you have two dynamic routes with an administrative distance of 120, you would specify an
administrative distance that is greater than 120 for the static route if you want the dynamic route to
override the static route.
Directly Connected Static Routes
You need to specify only the output interface (the interface on which all packets are sent to the
destination network) in a directly connected static route. The router assumes the destination is directly
attached to the output interface and the packet destination is used as the next hop address. The next-hop
can be an interface, only for point-to-point interfaces. For broadcast interfaces, the next-hop must be an
IPv4/IPv6 address.
Fully Specified Static Routes
You must specify either the output interface (the interface on which all packets are sent to the destination
network) or the next hop address in a fully specified static route. You can use a fully specified static route
when the output interface is a multi-access interface and you need to identify the next-hop address. The
next-hop address must be directly attached to the specified output interface.
Floating Static Routes
A floating static route is a static route that the router uses to back up a dynamic route. You must configure
a floating static route with a higher administrative distance than the dynamic route that it backs up. In
this instance, the router prefers a dynamic route to a floating static route. You can use a floating static
route as a replacement if the dynamic route is lost.
Note By default, a router prefers a static route to a dynamic route because a static route has a smaller
administrative distance than a dynamic route.
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