A network administrator configures a static route using only a next-hop IP address. Place the operational steps in the correct order that a Cisco IOS router performs to process and forward a packet using this recursive static route.
- 1The router receives an IPv4 packet and evaluates the destination address against the routing table to find the longest matching prefix.
- 2The router matches the static route entry and identifies the next-hop IPv4 address specified in the configuration.
- 3The router performs a recursive lookup in the routing table to resolve the next-hop IP address to an exit interface.
- 4The router queries the ARP table for the destination MAC address corresponding to the next-hop IPv4 address on the exit interface.
- 5The router encapsulates the packet into a new Layer 2 frame with the next-hop destination MAC address and transmits it out the exit interface.
Answer
The correct sequence of packet forwarding steps for a recursive static route is: 1) Evaluate destination against routing table for longest prefix match, 2) Identify matching static route and extract next-hop IP, 3) Perform recursive lookup to resolve next-hop IP to an exit interface, 4) Query ARP table for next-hop MAC address on that interface, 5) Encapsulate frame and forward out the exit interface.
When an IPv4 static route is configured using only a next-hop IP address, Cisco IOS must resolve the outgoing interface by performing a second (recursive) lookup in the routing table. First, the router matches the packet destination address to the static route entry. Second, it extracts the next-hop IP. Third, it recursively resolves that next-hop IP to a connected interface. Fourth, it uses ARP on that interface to determine the next-hop MAC address. Finally, it encapsulates the packet and forwards it out the interface.
Step-by-Step Solution
Key Concept
Recursive Static Route Lookup and Packet Forwarding Process