Assignment 12 – DHCP

Question 1

1. What IPv4 address values are commonly configured on a Windows Server or Client?

Answer 1

IP address, subnet mask, default gateway, DNS server(s)

Question 2

2. What are two methods that can be used to assign network address information to a computer system?

Answer 2

IP information can be either statically assigned or dynamically assigned.

Question 3

3. What are the four steps involved with a client obtaining IP settings through DHCP?

Answer 3

The client sends out a broadcast Discover packet to locate a DHCP server.

The DHCP server sends an Offer with a set of IP address values.

The client sends a Request to acquire the offered IP values.

The DHCP server sends an Acknowledgement to finalize the lease of address values.

DORA

Question 4

4. What needs to be configured on a local network when a DHCP server is located on a different subnet?

Answer 4

You either need to allow the forwarding of DHCP broadcasts on the router connecting the subnets together, or configure a server on the local subnet that acts as a DHCP Relay agent to allow DHCP requests to be forwarded to the appropriate subnet.

Question 5

5. What are the next steps in configuring a DHCP server after the role has been installed?

Answer 5

After installing the DHCP role, you need to set up a scope (range of IP addresses to hand out) and any other options such as default gateway, DNS servers, WINS servers, etc. You also need to Authorize the DHCP service to run.

Question 6

6. How many scopes per subnet are allowed?

Answer 6

Only one scope per subnet.

Question 7

7. What additional IP configuration options can be obtained through the DHCP process?

Answer 7

In addition to just an IP address and Subnet mask, you can assign the Default Gateway (Router) address and DNS Server Address(s).

Question 8

8. What are some of the context-sensitive icons used to reflect the DHCP server status?

Answer 8

A checkmark in a green circle indicates that the DHCP server is connected and authorized.

A red down arrow indicates that the DHCP server is
connected but not authorized.

A horizontal white line inside a red circle indicates that the DHCP server is connected, but the current user does not have the administrative credentials to manage the server.

An exclamation sign inside a yellow triangle indicates that 90 percent of the available addresses for server scopes are either in use or leased.

An exclamation sign inside a blue circle indicates 100 percent of the available addresses for server scopes are either in use or leased.

Question 9

9. What are exclusions with respect to DHCP address assignment?

Answer 9

An exclusion omits a range of addresses from being handed out during the DHCP process. An exclusion could be a single address or a range of addresses that might be assigned to devices requiring static address values. Reservations do not need to be included in an excluded range.

Question 10

10. What is required to create a DHCP reservation?

Answer 10

You require the MAC address of the Client for the reservation.

Question 11

13. What is the purpose of configuring filters with DHCP?

Answer 11

Filters allow or deny a range of computers from obtaining DHCP address settings. You require the MAC address of each computer.

Question 12

14. Describe a method for providing fault tolerance for DHCP on two subnets.

Answer 12

For fault tolerance with DHCP on two subnets, you would define two scopes on each DHCP server (one on each subnet) and use the 80/20 rule for providing exclusions on both subnets. If one of the DHCP servers fails, then clients on either subnet should be able to obtain addresses for the correct subnet from the other active DHCP server. Each subnet would still require a DHCP Relay Agent.

Question 13

Split Scope????

Answer 13

split scope is used to describe the fault tolerant method

Question 14

16. What term is used to describe an unauthorized DHCP server running on a subnet?

Answer 14

Any unauthorized DHCP server is called a Rogue DHCP server and can be a source of DOS attack.

Question 15

18. What are some DHCP statistics and their indication that can help troubleshoot DHCP issues?

Answer 15

Discovers are not increasing – possible hardware failure preventing DHCP requests from reaching the DHCP server. Adapter failure, cable disconnect, switch or router failure, or DHCP relay agent failure are possible problems.

Discovers increasing, Offers are static – Server is not responding to requests it receives. Possible faults include the server is out of addresses or the client or relay agent is outside the scope of the DHCP server.

Discovers and Offers increasing, but Requests not increasing – clients are accepting Offers from another Rogue DHCP server.