Static routing
Also known as: static routes
Static routing is the practice of manually configuring routes in a router's routing table instead of learning them from a routing protocol. The routes never change on their own, so an administrator must update them when the network topology changes.
A static route tells a router where to send traffic for a given destination network. The administrator supplies the destination prefix and mask, then either a next-hop IP address, an exit interface, or both. A default route — 0.0.0.0/0 with an IPv4 next hop, or ::/0 for IPv6 — is the most common static route of all, used to point everything the router does not otherwise know about toward an upstream gateway.
Static routes carry an administrative distance of 1, second only to a directly connected network at 0. That means a static route wins over any route learned by OSPF, EIGRP, or RIP for the same prefix. Raising the administrative distance on purpose creates a floating static route, which sits inactive in the background and installs itself only if the dynamically learned route disappears — a standard way to configure a backup path.
Route selection still follows the longest-prefix match rule. If the table holds both 10.1.0.0/16 and 10.1.5.0/24, a packet destined for 10.1.5.20 uses the /24 because it is the more specific match, regardless of how each route was learned. A static route also only stays in the table while its exit interface is up and its next hop is reachable.
The trade-offs are straightforward. Static routing consumes no CPU or bandwidth for routing updates, is fully predictable, and exposes no routing protocol to attack — which makes it a good fit for small networks, stub sites with a single uplink, and links to an ISP. It does not scale: every topology change requires manual edits on every affected router, and there is no automatic reconvergence when a path fails.
Static routing is core CCNA material in the IP connectivity domain. Expect configuration tasks and troubleshooting questions involving IPv4 and IPv6 static routes, default routes, floating statics, and reading a routing table to predict which route a packet will take.
Key takeaways
- Static routes are configured manually and do not update themselves when the topology changes.
- A route is defined by a destination prefix plus a next-hop address, an exit interface, or both.
- Static routes have an administrative distance of 1, so they take precedence over routes learned dynamically.
- A floating static route uses a raised administrative distance to serve as a backup for a dynamic route.
- Static routing suits small or stub networks and ISP links, but it does not scale and offers no automatic failover on its own.