Topic: 350-601 topic 1 question 261

Refer to the exhibit. Which action is taken to ensure that the relay agent forwards the DHCP BOOTREQUEST packet to a DHCP server?

A.
Configure the IP address of the DHCP server.
B.
Verify the DHCP snooping bindings.
C.
Configure the interface of the DHCP server as untrusted.
D.
Enable the DHCP relay agent.

Re: 350-601 topic 1 question 261

the answer is correct A

you can configure a DHCP server IP address on a layer 3 ethernet or subinterface. when an inbound DHCP BOOTREQUEST packet arrives on a port that is member of the port channel, the relay agent forward the packet to the IP address

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/4_0/dcnm/security/configuration/guide/sec_dcnm_config/sec_dhcpsnoop.pdf

Re: 350-601 topic 1 question 261

By process of elimination the correct answer is A: configure the ip add of the dhcp server

- verifying the dhcp snooping bindings does not confirm the relay agent forwards BOOTREQUEST packet
- "service dhcp" command is a deprecated command that has been replace by "ip dhcp relay" and has the purpose of enabling the dhcp relay agent (enabled by default)
- you would never configure the interfaces of the DHCP server as untrusted

Re: 350-601 topic 1 question 261

A looks correct.

Re: 350-601 topic 1 question 261

Answer is D

Deprecated the service dhcp command and replaced it with the ip dhcp relay command

Re: 350-601 topic 1 question 261

Indeed the correct ans in A. Below links confirms that DHCP relay is enabled by default.
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/6-x/security/configuration/guide/b_Cisco_Nexus_9000_Series_NX-OS_Security_Configuration_Guide/b_Cisco_Nexus_9000_Series_NX-OS_Security_Configuration_Guide_chapter_01101.html#:~:text=In%20DHCP%20relay%2C%20the%20circuit,field%20to%20the%20DHCP%20server.

Re: 350-601 topic 1 question 261

not sure you are reading....
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/7-x/security/configuration/guide/b_Cisco_Nexus_9000_Series_NX-OS_Security_Configuration_Guide_7x/b_Cisco_Nexus_9000_Series_NX-OS_Security_Configuration_Guide_7x_chapter_01100.html#concept_FB2E370D05B345658FC748ACAD9F9FD6

Configuring the DHCP Relay Source Interface
You can configure the source interface for the DHCP relay agent. By default, the DHCP relay agent uses the relay agent address as the source address of the outgoing packet. Configuring the source interface enables you to use a more stable address (such as the loopback interface address) as the source address of relayed messages.
Before you begin
Ensure that the DHCP feature is enabled.
Ensure that the DHCP relay agent is enabled.

Re: 350-601 topic 1 question 261

I would go with D

In provided example I do not see that dhcp relay agent is enable "ip dhcp relay". We have information that only "option" is enabled. From my understanding, without enablig relay agen, even if we have configured ip helper on interface, it will not work.
So configuration should looks like below

feature dhcp
ip dhcp relay
ip dhcp relay information option

interface ethernet 1/1
  ip dhcp relay address 10.0.0.10

Cisco doc.:
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/6-x/security/configuration/guide/b_Cisco_Nexus_9000_Series_NX-OS_Security_Configuration_Guide/b_Cisco_Nexus_9000_Series_NX-OS_Security_Configuration_Guide_chapter_01101.html#:~:text=a%20particular%20interface.-,Configuration%20Examples%20for%20DHCP,24%0A%09%09ip%20address%20172.16.31.254/24%20secondary%0A%09%09ip%20dhcp%20relay%20address%2010.55.11.3,-Additional%20References%20for

Re: 350-601 topic 1 question 261

A is the one!

Re: 350-601 topic 1 question 261

Tricky one, actually all the dhcp snooping config says nothing about the answer. DHCP relay to send requests to a DHCP server is made using the ip helper <dhcp ip> config.

Re: 350-601 topic 1 question 261

answer - A

When an inbound DHCP BOOTREQUEST packet arrives on a port that is a member of the port channel, the relay agent forwards the packet to the IP address specified.

BEFORE YOU BEGIN
By default, there is no DHCP server IP address configured on a Layer 3 interface.

Ensure that the DHCP server is correctly configured.

Determine the IP address of the DHCP server.

Ensure that DHCP snooping is enabled. For more information, see the "Enabling or Disabling the DHCP Snooping Feature" section.