CCIE Routing and Switching FAQ: IP Forwarding (Routing)

ccie-routing-switching-faq-ip-forwarding-routing

CCIE Routing and Switching FAQ: IP Forwarding (Routing)

Q1. What command is used to enable CEF globally for IPv4 packets?
A. enable cef
B. ip enable cef
C. ip cef
D. cef enable
E. cef enable ip
F. cef ip

Answer: C

Q2. What command is used to enable CEF globally for IPv6 packets?
A. enable cef6
B. ipv6 enable cef
C. ipv6 cef
D. ip cef (the command automatically enables CEF for IPv4 and IPv6)

Answer: C

Q3. Can CEF for IPv6 be enabled independently of CEF for IPv4?
A. Yes
B. No

Answer: B

Q4. Which of the following triggers an update to a CEF FIB?
A. Receipt of an ICMPv6 Neighbor Advertisement message with previously unknown information

B. Receipt of a LAN ARP reply message with previously unknown information

C. Addition of a new route to the IP routing table by EIGRP

D. Addition of a new route to the IP routing table by adding anip route command

E. The removal of a route from the IP routing table by EIGRP

Answer: C, D, and E

Q5. Which of the following triggers an update to a CEF adjacency table?
A. Receipt of a CDP multicast on the PVC connected to Router1

B. Receipt of an ARP response with previously unknown information

C. Receipt of a packet that needs to be routed to another router over a point-topoint interface

D. Receipt of an ICMPv6 Neighbor Advertisement with previously unknown information

Answer: B and D

Q6. Which of the following packet-switching paths is considered to be the slowest?
A. Process Switching
B. Fast Switching
C. Route Cache
D. Cisco Express Forwarding

Answer: A

Q7. Which of the following commands is used on a Cisco IOS Layer 3 switch to use the interface as arouted interface instead of a switched interface ?
A. ip routing oripv6 unicast-routing global command
B. ip routing oripv6 unicast -routing interface subcommand
C. ip address interface subcommand
D. switchport mode routed interface subcommand
E. no switchport interface subcommand

Answer: E

Q8. On a Cisco Catalyst 3560 switch, the first line of the output of ashow interface vlan 55 command lists the state as “Vlan 55 is down, line protocol is down.” Which of the following might be causing that state to occur?
A. VLAN interface has not beenno shut yet.

B. Theip routing global command is missing from the configuration.

C. On at least one interface in the VLAN, a cable that was previously plugged in has been unplugged.

D. VTP mode is set to transparent.

E. The VLAN has not yet been created on this switch, or is not in the active state.

Answer: E

Q9. On a Cisco Catalyst 3560 switch, the first line of the output of a show interface vlan 55 command lists the state as “Vlan 55 is up, line protocol is down.” Which of the following might be causing that state to occur?
A. VLAN interface has not beenno shut yet.

B. Theip routing global command is missing from the configuration.

C. There is no switch port on the switch with this VLAN allowed and in the STP forwarding state.

D. STP has been administratively deactivated for this VLAN.

E. The VLAN has not yet been created on this switch, or is not in the active state.

Answer: C

Q10. Imagine a route map used for policy routing, in which the route map has aset default interface serial0/0 command. Serial0/0 is a point-to-point link to another router. A packet arrives at this router, and the packet matches the policy routing route-map clause whose onlyset command is the one just mentioned. Which of the following general characterizations is true?
A. The packet will be routed out interface s0/0; if s0/0 is down, it will be routed using the default route from the routing table.

B. The packet will be routed using the default route in the routing table; if there is no default, the packet will be routed out s0/0.

C. The packet will be routed using the best match of the destination address with the routing table; if no match is found, the packet will be routed out s0/0.

D. The packet will be routed out interface s0/0; if s0/0 is down, the packet will be discarded.

Answer: C

Q11. Router1 has an fa0/0 interface and two point-to-point WAN links back to the core of the network (s0/0 and s0/1, respectively). Router1 accepts routing information only over s0/0, which Router1 uses as its primary link. When s0/0 fails, Router1 uses policy routing to forward the traffic out the relatively slower s0/1 link. Which of the followingset commands in Router1’s policy routing route map could have been used to achieve this function?
A. set ip default next-hop
B. set ip next-hop
C. set default interface
D. set interface

Answer: A and C

About the author

Scott

Leave a Comment