Router R1 exists in an Enterprise that uses EIGRP as its routing protocol. The show ip route command output on router R1 lists the following phrase: "Gateway of last resort is 1.1.1.1 to network 2.0.0.0".
Whic h of the following is most likely to have caused this output to occur on R1?（）

多项选择题In a lab, R1 connects to R2, which connects to R3. R1 and R2 each have several working interfaces, all assigned addresses in class A network 10.0.0.0. Router R3 has some working interfaces in class A net work 10.0.0.0, and others in class B network 172.16.0.0. The engineer experiments with the auto -summary command on R2 and R3, enabling and disabling the command in various combinations. Which of the following combinations will result in R1 seeing a rout e for 172.16.0.0 16, instead of the individual subnets of class B network 172.16.0.0?（）

A. auto - summary on R2 and no auto - summary on R3
B. auto - summary on R2 and auto - summary on R3
C. no auto -summary on R2 and no auto- summary on R3
D. no auto - summary on  R2 and auto - summary on R3

单项选择题R1 has 5 working interfaces, with EIGRP neighbors existing off each interface. R1 has routes for subnets 10.1.1.0 24, 10.1.2.0 24, and 10.1.3.0 24, with EIGRP integer metrics of roughly 1 million, 2 million, a nd 3 million, respectively. An engineer then adds the ip summary - address eigrp 1 10.1.0.0 255.255.0.0 command to interface Fa0 0. Which of the following is true?（）

A. R1 loses and then reestablishes neighborships with all neighbors.
B. R1 no longer advert ises 10.1.1.0/24 to neighbors connected to Fa0/0.
C. 1 advertises a 10.1.0.0/16 route out Fa0/0, with metric of around 3 million (largest metric of component subnets).
D. R1 advertises a 10.1.0.0/16 route out Fa0/0,with metric of around 2 million (med ian metric of component subnets).

单项选择题An engineer plans to configure summary routes with the ip summary - address eigrp asn prefix mask command. Which of the following, when added to such a command, would create a summary that includes all four of the following subnets: 10.1.100.0 25, 10.1.101.96 27, 10.1.101.224 28, and 10.1.100.128.25?（）

A. 10.1.0.0 255.255.192.0
B. 10.1.64.0 255.255.192.0
C. 10.1.100.0 255.255.255.0
D. 10.1.98.0 255.255.252.0

多项选择题An engineer has typed four different single - line prefix lists in a word processor. The four answers show the four different single -lin e prefix lists. The engineer then does a copy paste of the configuration into a router. Which of the lists could match a subnet whose prefix length is 27?（）

A. ip prefix - list fred permit 10.0.0.0/24 ge 16 le 28
B. ip prefix - list barney permit 10.0.0.0/24 le 28
C. ip prefix - list wilma permit 10.0.0.0/24 ge 25
D. ip prefix - list betty permit 10.0.0.0/24 ge 28

单项选择题R1 has correctly configured EIGRP to filter routes using a route map named question. The configuration that follows shows the entire route map and related configuration. Which of the following is true regarding the filtering action on prefix 10.10.10.0 24 in this case?（） route - map question deny 10 match ip address 1 route - map question permit 20 match ip address prefix- list fred ! access - list 1 deny 10.10.10.0 0.0.0.255 ip prefix - list fred permit 10.10.10.0 23 le 25

A. It will be filtered due to the deny action in route map clause 10
B. It will be allowed because of the double negative (two deny references) in clause 10
C. It will be permitted due to matching clause 20's reference to prefix - list freD
D.  It will be filtered due to matching the implied deny all route map clause at the end of the route map