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Which two statements are true?

Refer to the exhibit.

Which two statements are true? (Choose two)

PrepAway - Latest Free Exam Questions & Answers

A.
DHCPDISCOVER packets will reach the DHCP server.

B.
The router will not forward DHCPDISCOVER packets because it has not been configured
to do so.

C.
This configuration is applied to interface Fa0/1.

D.
DHCPDISCOVER packets will not reach the DHCP server because DHCPDISCOVER
packets are broadcasts.

E.
DHCPDISCOVER packets will not reach the DHCP server because ports 67 and 68 have
not been explicitly allowed by the ip forward-protocol command.

F.
This configuration is applied to interface Fa0/0.

Explanation:
While routers accept and generate broadcasts, they do not forward them. This can be quite
a problem when a broadcast needs to get to a device such as a DHCP or TFTP server that’s
on one side of a router with other subnets on the other side.

If this PC attempts to locate a DNS server with a broadcast, the broadcast will be stopped by
the router and will never get to the DNS server. By configuring the ip helper-address
command on the router, UDP broadcasts such as this will be translated into a unicast by the
router, making the communication possible. The command should be configured on the
interface that will be receiving the broadcasts.
R1(config)#int e0
R1(config-if)#ip helper-address ?
A.B.C.D IP destination address
R1(config-if)#ip helper-address 10.1.1.1
This command does forward eight common UDP service broadcasts by default.
• TIME, port 37
• TACACS, port 49
• DNS, port 53
• BOOTP/DHCP Server, port 67
• BOOTP/DHCP Client, port 68
• TFTP, port 69
• NetBIOS name service, port 137
• NetBIOS datagram service, port 138
That’s going to cover most scenarios where the ip helper-address command will be useful,
but what about those situations where the broadcast you need forwarded is not on this list?
You can use the ip forward-protocol command to add any UDP port number to the list. In
this particular case, ports 67 and 68 were not included, so the BOOTP packets will not be
sent to the DHCP server.

4 Comments on “Which two statements are true?

  1. KurpeusLondon says:

    This is completly wrong. D and F are correct. DHCP discovers are bcast packets so they stop at the router. The router relay the packet as unicast to the dhcp server.

    helper udp 67 and 68 are enabled by default enable.

    This should be enable to the client facing interface.




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