ccna certification practice questions

ccna certification practice questions.For Ethernet, to successfully encapsulate an Ethernet frame, the mapping of the MAC address at Layer 2 to the IP address at Layer 3 must be done through the ARP protocol. If a static route with next-hop address configuration is used, the content of the ARP request broadcast packet asks for the MAC address of the next-hop address, so the next-hop router answers the ARP with the MAC address of its own Ethernet interfaceo But in Ethernet, if the configuration of a static route with a send-out interface is used by the promo, if there is no corresponding ARP entry in the ARP table of R4, and the outgoing ARP broadcast packet without a device reply, the Ethernet frame will not be successfully encapsulated. However, by default, the router's Ethernet interfaces are enabled with the ARP proxy function, so when R4 sends an ARP query, R3 receives the ARP query and looks at its own routing table, and if there is a route entry for the destination address in the routing table, it responds with the MAC address of its own Ethernet interface G0/0, enabling R4 to encapsulate the Ethernet frame successfully. If you turn off the ARP proxy function on router R3's Ethernet interface G0/0 and turn on debug, you will see the encapsulation failure message,I,. R3(config)#interface GigabitEthernetO/O R3(config-if)#no ip proxy-arp Disable the ARP proxy functionR4#debug ip packet R4#clear arp debug R4#ping 172,16.1.1///clear ARP tableTypeescape sequence to abort. Sending 5,1 OO-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:.Apr 24 07:52:58.990: IP:tableid=0,s=l 72.16.34.4 (local),d=172.16.1.1 (GigabitEthemetO/O), routed via RIB *Apr 24 07:52:58.990: IP: s= 172.1634. 4 (local), d=172J6.1.1 (GigabitEthemetO/O), len 100, sending .Apr 2407:52:58.990: IP: 8=172.16.34.4 (local), d=172.16.1.1 (GigabitEthemetO/O), len 100, encapsulation failed. Packet encapsulation failed.66. Cisco Networking Lab CCNA Lab Guide (Version 2)Zun [mention while 1 For static route configuration with a send-out interface, if the outgoing interface is an Ethernet interface, it is recommended to use both the next-hop address and the send-out interface to configure, as follows:R4(config)#ip route 0.0.0.0 0.0.0.0.0 GigabitEthernet0/0 172.16.34.3(3) Dynamically Viewing the Routing Table Addition or Removal Process