Static Route Not in Routing Table After Configuration
Presenting Symptom
A static route configured on a Cisco router does not appear in the routing table.
Network Context
A small branch office with a Cisco 4321 router (IOS XE 16.9) connects to the corporate HQ via a serial link (PPP). The router has a directly connected serial interface (Serial0/0/0) with IP 10.1.1.1/30, and a GigabitEthernet0/0/0 interface (192.168.1.1/24) for the LAN. The engineer configured a static route to reach the HQ LAN (172.16.0.0/24) via next-hop 10.1.1.2, but 'show ip route' does not display the route.
Diagnostic Steps
Check the routing table for the static route
show ip route staticNo output or only default routes if any.
If the static route is missing, it may not have been entered correctly, or the next-hop is unreachable.
Verify the static route configuration
show running-config | include ip routeip route 172.16.0.0 255.255.255.0 10.1.1.2
Confirm the static route is present in the running config. If not, it was never configured or was removed.
Check the next-hop reachability
show ip route 10.1.1.2Routing entry for 10.1.1.0/30, known via "connected", directly connected, Serial0/0/0
If the next-hop is not reachable (e.g., no route to 10.1.1.2), the static route will not be installed. Ensure the serial interface is up/up and has correct IP.
Check interface status and IP configuration
show ip interface briefSerial0/0/0 10.1.1.1 YES manual up up
If the interface is down/down, the static route cannot be installed. Also verify the IP address matches the next-hop network.
Root Cause
The static route is configured with an incorrect next-hop IP address (e.g., 10.1.1.3 instead of 10.1.1.2), or the next-hop interface is down, making the next-hop unreachable. In this case, the next-hop IP was mistyped as 10.1.1.3.
Resolution
Verification
Verify the static route appears in the routing table: show ip route static Expected output: S 172.16.0.0/24 [1/0] via 10.1.1.2 Also ping the HQ LAN to confirm connectivity: ping 172.16.0.1
Prevention
1. Always double-check next-hop IP addresses when configuring static routes. 2. Use exit interface instead of next-hop IP for point-to-point links to avoid ARP issues. 3. Implement a change management process that includes verification of routing tables after configuration changes.
CCNA Exam Relevance
On the CCNA 200-301 exam, this scenario tests understanding of static route installation conditions: the route must have a valid next-hop reachable via a directly connected network. Exam questions may present a 'show ip route' output missing a static route and ask for the cause (e.g., next-hop unreachable, incorrect subnet mask).
Exam Tips
Remember that a static route is only installed if the next-hop IP is reachable via a directly connected route.
If a static route uses an exit interface (e.g., Serial0/0/0), it does not require a next-hop IP and is always installed if the interface is up.
Use 'show ip route static' to filter only static routes; 'show ip route' shows all routes.
Commands Used in This Scenario
show ip interface brief
Displays a summary of all IP interfaces on the device, including their IP address, status, and protocol state, used for quick verification of interface configuration and connectivity.
show ip route
Displays the current IP routing table on a Cisco router, used to verify routes, check next-hop addresses, and troubleshoot connectivity issues.
show running-config
Displays the current active configuration in DRAM, showing all non-default settings.
Test Your CCNA Knowledge
Practice with scenario-based questions to prepare for the CCNA 200-301 exam.
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