FAQ ON STATIC-DEFAULT# INTERVIEW PREP GUIDE ABOUT STATIC AND DEFAULT ROUTING
🔹 Why is static routing used ?
It provides simple, predictable, and secure routing in small networks.
🔹 Where is static routing commonly used ?
Small office networks, Branch offices and Stub networks.
🔹 How do you identify that static routing is used in a network ?
Routes are manually configured without dynamic routing protocols.
🔹 What is the main advantage of static routing ?
No routing protocol overhead.
🔹 How does static routing improve security ?
Routes are not advertised, reducing exposure.
🔹 Can static routing be used with dynamic routing ?
Yes, In hybrid network.
🔹 What is a recursive static route ?
A route where the next-hop IP is resolved through another route.
🔹 What is a directly connected static route ?
A route using the exit interface instead of next-hop IP.
🔹 What is floating static routing ?
A backup route with higher administrative distance.
ip route 'network' 'mask' 'next-hop' 'AD'
🔹 What is administrative distance (AD) ?
A value use to select the most preferred route.
🔹 What is a next-hop static route ?
Route defined using next hop IP address.
🔹 What is fully specified static route ?
Include both next-hop IP Address and exit interface.
🔹 Why use higher AD for backup routes ?
To ensure primary route is preferred.
🔹 What is the formula for route selection ?
Best Route = lowest AD → longest Prefix Match.
🔹 What is longest prefix match ?
Route with the most specific subnet mask is selected.
🔹 How does default routing simplify design ?
Reduce the routing table size and configuration complexity.
🔹 Can static routing support load balancing ?
Yes (equal-cost routes).
🔹 How to achieve redundancy with static routing ?
Use floating static routes.
🔹 How to detect failure in static routing ?
Using tracking (IP SLA: Monitors reachability of next-hop).
🔹 Why is default routing used ?
To send traffic to a gateway of last resort.
🔹 What is gateway of last resort ?
The router used for unknown destinations.
🔹 What happens if default route is not configured ?
Unknown traffic is dropped.
🔹 How to troubleshoot default route issues ?
Check gateway reachability.
🔹 Can default routing be used in large networks ?
Yes, at edge routers.
🔹 Is static routing more secure than dynamic routing ?
Yes, as it does not advertise routes.
🔹 How does default routing impact security ?
All unknown traffic goes to one gateway—needs filtering.
🔹 What is route filtering in static routing ?
Manually controlling allowed paths.
🔹 Can multiple default routes exist ?
Yes, for redundancy.
🔹 What is hybrid routing ?
Combination of static and dynamic routing.
🔹 What is ECMP in static routing ?
Equal-cost multiple paths for load balancing.
🔹 How do static and default routing work together ?
- Static routes handle known networks (Static routes for internal networks).
- Default handles unknown (Default route for internet).
🔹 What is the best use case of static + default routing ?
Branch office with internet access.
🔹 What is route summarization in static routing ?
Combining multiple routes into one.
🔹 Formula for summarization: ?
Find common bits in subnet → define summary network
🔹 How to reduce routing table size ?
Use default route + summarization.
🔹 If multiple paths exist, what is preferred ?
Static + floating static or dynamic routing.
🔹 What is best practice for static routing ?
Use minimal routes, add redundancy, monitor reachability.
🔹 What is the future of static and default routing ?
They will continue to be used in small networks, edge networks, and backup routing designs.
