You save the configuration on a router with the copy running-config startup-config command and reboot the router. The router, however, comes up with a blank configuration. What can the problem be?

You have your laptop directly connected into a router's Ethernet port. Which of the following are among the requirements for the copy flash tftp command to be successful?
1. TFTP server software must be running on the router.
2. TFTP server software must be running on your laptop.
3. The Ethernet cable connecting the laptop directly into the router's Ethernet port must be a straight-through cable.
4. The laptop must be on the same subnet as the router's Ethernet interface.
5. The copy flash tftp command must be supplied the IP address of the laptop.

What information is displayed by the show hosts command?
1. Temporary DNS entries
2. The names of the routers created using the hostname command
3. The IP addresses of workstations allowed to access the router
4. Permanent name-to-address mappings created using the ip host command
5. The length of time a host has been connected to the router via Telnet

You are unsuccessful in telnetting into a remote device. What could the problem be?
1. IP addresses are incorrect.
2. Access control list is filtering Telnet.
3. There is a defective serial cable.
4. The VTY password is missing.

Which three commands can be used to check LAN connectivity problems on a router?
1. show interfaces
2. show ip route
3. tracert
4. ping
5. dns lookups