The answer is a missing static route on the ASA. This is correct because the "No route to host" drop occurs specifically when the Cisco ASA receives a packet destined for an IP address that does not match any entry in its routing table; the firewall cannot forward the packet at Layer 3 and must drop it, generating the corresponding syslog message. On the Cisco SCOR / CCNP Security Core 350-701 exam, this question tests your understanding of the ASA’s packet processing order, where route lookup happens after NAT but before access control list evaluation—a common trap is confusing this drop with an ACL deny or a NAT failure. Remember that a "No route to host" drop is always a routing problem, not a security policy issue. A helpful memory tip: "No route, no host—check the table first, not the ACL list."
350-701 Security Concepts Practice Question
This 350-701 practice question tests your understanding of security concepts. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
Exhibit
show asp drop
Frame drop:
No route to host 100
Access list deny 50
Flow blocked (other) 0
Flow drop:
No valid session 20
Stateful ACL check failed 5
Cluster drop: 0
Refer to the exhibit. What is the most likely reason for the high number of 'No route to host' drops on a Cisco ASA?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
show asp drop
Frame drop:
No route to host 100
Access list deny 50
Flow blocked (other) 0
Flow drop:
No valid session 20
Stateful ACL check failed 5
Cluster drop: 0
A
Firewall is in transparent mode
Why wrong: Transparent mode does not require routing; it bridges traffic.
B
Interface is down
Why wrong: If the interface were down, the drop reason would be 'interface not up' or similar.
C
Missing static route on the ASA
Without a route to the destination, the ASA cannot forward the packet.
D
Incorrect NAT rule
Why wrong: NAT issues would cause drops like 'no translation' or 'no xlate', not 'no route to host'.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Missing static route on the ASA
The 'No route to host' drop on a Cisco ASA indicates that the firewall has no valid route in its routing table to reach the destination IP address of the packet. Option C is correct because a missing static route (or dynamic route) for the destination network prevents the ASA from performing a route lookup, causing it to drop the packet with this specific syslog message. This is a Layer 3 forwarding issue, not a policy or NAT problem.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
Firewall is in transparent mode
Why it's wrong here
Transparent mode does not require routing; it bridges traffic.
✗
Interface is down
Why it's wrong here
If the interface were down, the drop reason would be 'interface not up' or similar.
✓
Missing static route on the ASA
Why this is correct
Without a route to the destination, the ASA cannot forward the packet.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
Incorrect NAT rule
Why it's wrong here
NAT issues would cause drops like 'no translation' or 'no xlate', not 'no route to host'.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the distinction between Layer 3 routing drops ('No route to host') and Layer 2/interface drops, or between routing issues and NAT/policy failures, so candidates must remember that 'No route to host' is exclusively a routing table lookup failure, not a firewall rule or interface problem.
Trap categories for this question
Similar concept trap
If the interface were down, the drop reason would be 'interface not up' or similar.
Detailed technical explanation
How to think about this question
The ASA performs a route lookup using its Forwarding Information Base (FIB) derived from the routing table; if no matching route exists for the destination, the packet is dropped with the 'No route to host' syslog message (message ID 106023). This can happen even if a default route is present but the destination is a specific host on a directly connected subnet that is not in the routing table — for example, when a next-hop router is unreachable or a static route is missing for a remote network. In real-world scenarios, this often occurs after a network change where a static route was removed or a dynamic routing protocol (e.g., OSPF) fails to propagate the route.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Security Concepts — This question tests Security Concepts — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Missing static route on the ASA — The 'No route to host' drop on a Cisco ASA indicates that the firewall has no valid route in its routing table to reach the destination IP address of the packet. Option C is correct because a missing static route (or dynamic route) for the destination network prevents the ASA from performing a route lookup, causing it to drop the packet with this specific syslog message. This is a Layer 3 forwarding issue, not a policy or NAT problem.
What should I do if I get this 350-701 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This 350-701 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 350-701 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.