Ch23-IPv4 TSHOOT TOOLS

Question 1

An ICMP echo message and reply, often used in IP networks to test reachability of a device

Answer 1

ping

Question 2

A program available on many systems that traces the patch a packet takes to a destination, often used to troubleshoot routing problems between hosts

Answer 2

traceroute

Question 3

One type of ICMP message, created specifically to be used as the message sent to test connectivity in a network. These messages are sent to other hosts, expecting the other host to reply

Answer 3

ICMP echo request

Question 4

One type of ICMP message, created specifically to be used as the message returned when testing connectivity in a network. These messages are expected to be received from other hosts in response to echo request messages

Answer 4

ICMP echo reply

Question 5

An IOS command in which the ping command accepts many other parameters besides just the destination IP address

Answer 5

extended ping

Question 6

From one host’s perspective, the route over which a packet travels from that host to some other host

Answer 6

forward route

Question 7

From one host’s perspective, for packets sent back to the host from another host, the route over which the packet travels

Answer 7

reverse route

Question 8

Consider a scenario as shown in the attached image. Host A cannot reach Host B. Host A is not accessible for testing, so the engineer tests standard pings from router R1 to Host B. The ping is successful. What would consititute a better test of Host A’s issue and why?

Answer 8

In this scenario, R1 will ping from it’s outgoing interface S0/0/0. If B responds, then the reverse route from Host B to R1 S0/0/0 is proven, but the test does not prove that Host B can reach Host A’s subnet.

An extended ping from R1 G0/0, which is part of Host A’s subnet, could test the reverse route from Host B back to A’s subnet, and would be a more accurate test of the problem.

Question 9

An engineer performed a traceroute between a client device and a destination host. According to the engineer’s documentaion, 5 routers exist between the source and destination. The traceroute command did not complete, but the engineer has access to all 5 routers. Which routers should be investigated for problems?

Answer 9

Following the traceroute output, the last router that responded should be examined for forward routing issues.

The next router that should have been listed should be examined for reverse route issues.