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Difficulty: MediumIPv4 Static Routing

A network administrator needs to configure and verify a floating static route for destination network 172.16.20.0/24172.16.20.0/24 via next-hop IP 10.2.2.210.2.2.2 on a Cisco router. The primary path to this network is currently learned dynamically via EIGRP with an Administrative Distance of 9090. Place the configuration and verification steps in the correct sequential order from first to last.

  1. 1Enter global configuration mode on the router using the `configure terminal` command.
  2. 2Configure the backup static route using `ip route 172.16.20.0 255.255.255.0 10.2.2.2 100` to set its Administrative Distance higher than EIGRP.
  3. 3Execute `show ip route` in privileged EXEC mode to confirm that only the primary EIGRP route appears in the routing table while the primary link is healthy.
  4. 4Issue `shutdown` on the primary outbound interface to simulate a link failure.
  5. 5Re-run `show ip route` to confirm that the floating static route via 10.2.2.210.2.2.2 is now active in the routing table.

Answer

The correct sequential process is: Enter global configuration mode -> Configure the floating static route with AD 100 -> Verify the routing table to ensure the route is inactive during normal operation -> Shut down the primary interface to trigger failover -> Re-verify the routing table to confirm the floating static route becomes active.
The correct order follows standard Cisco IOS workflow: configuring global settings first, adding the floating static route with an AD higher than EIGRP (90), verifying that the route is inactive during normal operation, simulating a link failure by shutting down the primary interface, and finally verifying that the floating static route takes over as the active path in the routing table.

Step-by-Step Solution

1
Enter global configuration mode
The CLI prompt changes to global configuration mode (`Router(config)#`).
Static routing commands (`ip route`) can only be entered in global configuration mode.
2
Configure the backup static route
The floating static route with Administrative Distance 100 is written to the running configuration.
Configuring an Administrative Distance of 100 ensures the static route has a higher distance than EIGRP (AD 90), keeping it out of the routing table during normal operation.
3
Verify initial routing table state
The output of `show ip route` lists only the EIGRP route for 172.16.20.0/24172.16.20.0/24.
Cisco IOS selects routes with the lowest Administrative Distance for the Routing Information Base (RIB); thus, the floating static route must remain hidden while EIGRP is healthy.
4
Simulate primary path failure
The primary interface enters the administratively down state, invalidating and removing the primary EIGRP route from the RIB.
Interface shutdown removes dependent routes, prompting the router to evaluate alternative routes for the destination.
5
Verify post-failover routing table state
The output of `show ip route` shows 172.16.20.0/24172.16.20.0/24 reachable via static route next-hop 10.2.2.210.2.2.2.
With the primary route removed, the floating static route becomes the best remaining path and is installed into the active routing table.

Key Concept

Floating static route configuration, administrative distance precedence, and failover verification.
Estimated Time:1m 30s
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Topics

IPv4 Static Routing

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