Correct Answer: It is used to bypass the configuration in NVRAM.
Explanation:
The default configuration setting is
0x2102, which tells the router to load the IOS from flash and the configuration from NVRAM.
0x2142 tells the router to bypass the configuration in NVRAM so that you can perform password recovery.
2. Which command will show you the IOS version running on your router?
The best answer is
show version, which shows you the IOS file running currently on your router. The
show flash command shows you the contents of flash memory, not which file is running.
3. A network administrator is connecting hosts A and B directly through their Ethernet interfaces, as shown in the illustration. Ping attempts between the hosts are unsuccessful. What can be done to provide connectivity between the hosts?
A crossover cable should be used in place of the straight-through cable.
A rollover cable should be used in place of the straight-through cable.
The subnet masks should be set to 255.255.255.192.
First, if you have two hosts directly connected, as shown in the graphic, then you need a crossover cable. A straight-through cable won't work. Second, the hosts have different masks, which puts them in different subnets. The easy solution is just to set both masks to 255.255.255.0 (/24).
4. If a host on a network has the address 172.16.45.14/30, what is the subnetwork this host belongs to?
A /30, regardless of the class of address, has a 252 in the fourth octet. This means we have a block size of 4 and our subnets are 0, 4, 8, 12, 16, etc. Address 14 is obviously in the 12 subnet.
5. Using the illustration from the previous question, what would be the IP address of S0 if you were using the first subnet? The network ID is 192.168.10.0/28 and you need to use the last available IP address in the range. Again, the zero subnet should not be considered valid for this question.
A /28 is a 255.255.255.240 mask. The first subnet is 16 (remember that the question stated not to use subnet zero) and the next subnet is 32, so our broadcast address is 31. This makes our host range 17-30. 30 is the last valid host.
6. A network administrator wants to upgrade the IOS of a router without removing the image currently installed. What command will display the amount of memory consumed by the current IOS image and indicate whether there is enough room available to hold both the current and new images?
The
show flash command will provide you with the current IOS name and size and the size of flash memory.
7. You are troubleshooting a connectivity problem in your corporate network and want to isolate the problem. You suspect that a router on the route to an unreachable network is at fault. What IOS user exec command should you issue?
The command
traceroute (trace for short), which can be issued from user mode or privileged mode, is used to find the path a packet takes through an internetwork and will also show you where the packet stops because of an error on a router.
8. You copy a configuration from a network host to a router's RAM. The configuration looks correct, yet it is not working at all. What could the problem be?
Options
A. You copied the wrong configuration into RAM.
B. You copied the configuration into flash memory instead.
C. The copy did not override the shutdown command in running-config.
D. The IOS became corrupted after the copy command was initiated.
Correct Answer: The copy did not override the shutdown command in running-config.
Explanation:
Since the configuration looks correct, you probably didn't screw up the copy job. However, when you perform a copy from a network host to a router, the interfaces are automatically shut down and need to be manually enabled with the
no shutdown command.
9. If you want to have more than one Telnet session open at the same time, what keystroke combination would you use?
To keep open one or more Telnet sessions, use the
Ctrl+Shift+6 and then
X keystroke combination.
10. The corporate office sends you a new router to connect, but upon connecting the console cable, you see that there is already a configuration on the router. What should be done before a new configuration is entered in the router?
Options
A. RAM should be erased and the router restarted.
B. Flash should be erased and the router restarted.
C. NVRAM should be erased and the router restarted.
D. The new configuration should be entered and saved.
Correct Answer: NVRAM should be erased and the router restarted.
Explanation:
Before you start to configure the router, you should erase the NVRAM with the
erase startup-config command and then reload the router using the
reload command.