Cisco 300-410 Exam - Topic 6 Question 120 Discussion

Actual exam question for Cisco's 300-410 exam

Question #: 120
Topic #: 6

Which configuration feature should be used to block rogue router advertisements instead of using the IPv6 Router Advertisement Guard feature?

AVACL blocking broadcast frames from nonauthorized hosts

BPVLANs with promiscuous ports associated to route advertisements and isolated ports for nodes

CPVLANs with community ports associated to route advertisements and isolated ports for nodes

DIPv4 ACL blocking route advertisements from nonauthorized hosts

Show Suggested Answer

Suggested Answer: B

The IPv6 Router Advertisement Guard feature provides support for allowing the network administrator to block or reject unwanted or rogue router advertisement guard messages that arrive at the network device platform. Router Advertisements are used by devices to announce themselves on the link. The IPv6 Router Advertisement Guard feature analyzes these router advertisements and filters out router advertisements that are sent by unauthorized devices.

Certain switch platforms can already implement some level of rogue RA filtering by the administrator configuring Access Control Lists (ACLs) that block RA ICMP messages that might be inbound on ''user'' ports.

by Alethea at Jan 05, 2026, 05:16 AM

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Fabiola

5 hours ago

I think option C is the right choice.

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Kimbery

5 days ago

Option C is the way to go, for sure. Gotta love those isolated ports for the nodes. Keeps everything nice and tidy.

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Merilyn

10 days ago

Haha, A? Really? Blocking broadcast frames? That's like trying to stop a freight train with a toothpick.

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Aja

1 month ago

D is the obvious answer here. IPv4 ACLs are the way to block those pesky router ads. Simple and effective.

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Antonette

1 month ago

I'm torn between B and C, but I think C might be the better choice. Gotta keep those community ports secure, you know?

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Billi

1 month ago

Option B looks like the way to go. Blocking rogue router ads with PVLANs sounds like a solid plan.

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Dulce

2 months ago

I feel like I should know this, but I keep mixing up the different types of ACLs and their applications. Is it really about blocking unauthorized hosts?

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Truman

2 months ago

I’m leaning towards option C, but I’m not entirely confident. I recall something about community ports being used for specific traffic types.

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Alona

2 months ago

This question feels similar to one we practiced on rogue DHCP servers. I wonder if the answer is related to how we isolate ports in PVLANs.

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Louis

2 months ago

I think I remember something about using PVLANs, but I'm not sure if it's community or promiscuous ports that are relevant here.

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Deandrea

2 months ago

I've got a good feeling about this one. The key is understanding how the different VLAN and ACL configurations can be used to mitigate rogue router advertisements.

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Adelle

2 months ago

This looks like it's testing our knowledge of IPv6 security features. I'm going to review the details of each option and try to eliminate the ones that don't directly address rogue router advertisements.

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Jenise

3 months ago

I'm a bit confused by the wording of this question. Can someone clarify the difference between the IPv6 Router Advertisement Guard and the other choices?

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Paris

3 months ago

Okay, I remember learning about PVLAN configurations for securing router advertisements. I think option C might be the way to go here.

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Delfina

3 months ago

Hmm, this seems like a tricky one. I'll need to think carefully about the differences between the IPv6 Router Advertisement Guard feature and the other options.

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