9 Apr, 2007
Networking Interview Questions
- A default route is analogous to a _________.
* default gateway
* static route
* dynamic route
* one-way route
Correct answer: A
A default route is analogous to a default gateway. It is used to reduce the length of routing tables and to provide complete routing capabilities when a router might not know the routes to all other networks.
- Routers can learn about destinations through static routes, default, or dynamic routing. By default, a router will use information derived from __________.
* IGRP
* RIP
* IP
* TCP
Correct answer: A
The quality of information is rated:
Connected interface 0
Static route 1
IGRP 100
RIP 120
Unknown 255
The lower the value, the more reliable the source with 255 signifying information that the router will ignore. So, the router will use IGRP, rated at 100, before RIP, rated at 120.
- You are logged into a router, what command would show you the IP addresses of routers connected to you?
* show cdp neighbors detail
* show run
* show neighbors
* show cdp
Correct answer: A
- As a system administrator, you perform an extended ping at the privileged EXEC prompt. As part of the display, you see “Set DF bit in IP header? [yes] :” What would happen if you answered no at the prompt.
* This lets the router fragment the packet.
* It tells the router not to fragment the packet.
* This lets the router direct the packet to the destination it finds in its routing table.
* It tell the router to send the packet to the next hop router
Correct answer: A
“Set DF bit in IP header?” is a response to an extended ping at the router. If you answer yes (the default) the router will not fragment the packet. If you answer no, the router will fragment the packet.
- You have typed “ping” 172.16.101.1 and get the following display: Type escape sequence to abort. Sending 5, 100-byte ICMP Echoes to 172.16.101.1, timeout is 2 seconds:
.!!!!
What does the “.” signify?
* That one message timed out.
* That all messages were successful.
* That one message was successful.
* That one message completed in under the allotted timeframe.
Correct answer: A
The possible responses from the ping command are: ! Successful receipt of an echo reply. Timed out waiting for a reply U Destination unreachable C Congestion-experienced packet I Ping interrupted ? Packet type unknown & Packet TTL exceeded
- Which command, that is used to test address configuration, uses Time-To-Live (TTL) values to generate messages from each router.
* trace
* ping
* telnet
* bootp
Correct answer: A
The Cisco IOS EXEC command “trace [protocol] [destination]” is used to discover routes that packets will travel to their destination hosts. Trace uses TTL (Time to Live) values to report destination route information.
- What does the command “IP name-server 255.255.255.255″ accomplish? * It sets the domain name lookup to be a local broadcast.
* This is an illegal command.
* It disables domain name lookup.
* The command is now defunct and has been replaced by “IP server-name ip any”
Correct answer: A
By default DNS is enabled on a router with a server address of 255.255.255.255, which provides for a local broadcast.
- As a system administrator, you need to provide your routers with a Domain Name System (DNS) server. How many DNS servers can you specify with one command?
* 6
* 1
* 2
* 4
Correct answer: A
You can only specify six name servers in one command. The syntax is “IP name-server server-address1 [[ server-address2 ]…server-address6]. You must also enable
DNS.
- How would you configure one host name that points to two IP addresses?
* IP host jacob 1.0.0.5 2.0.0.8
* IP jacob 1.0.0.5 2.0.0.8
* IP host jacob 1.0.0.5
* IP host duplicate “all”
Correct answer: A
The correct syntax is IP host name [ TCP-port-number ] address [ address ]….. So, “IP host P1R1 1.0.0.5 2.0.0.8″ is the correct choice. “IP host jacob 1.0.0.5″ only points the host name jacob to one IP address–1.0.0.5.
- The following selections show the command prompt and the configuration of the IP network mask. Which two are correct?
* Router#term IP netmask-format { bitcount | decimal | hexadecimal }
* Router(config-if)#IP netmask-format { bitcount | decimal | hexadecimal }
* Router(config-if)#netmask-format { bitcount | decimal | hexadecimal }
* Router#ip netmask-format { bitcount | decimal | hexadecimal }
Correct answer: A & B
Router#term IP netmask-format { bitcount | decimal | hexadecimal } and Router(config-if)#IP netmask-format { bitcount | decimal | hexadecimal } are correct. You can configure the mask for the current session and you can configure it for a specific line.
- When configuring the subnet mask for an IP address, which formats can be used?
* dotted-decimal.
* Hexadecimal
* Bit-count
* Octal
* Binary
Correct answer: A, B &C
