- A
DenyGroups sshusers
Why wrong: Denies the group, opposite of what is needed.
- B
AllowGroups sshusers
Allows only members of sshusers group.
- C
AllowUsers sshusers
Why wrong: AllowUsers expects usernames, not groups.
- D
Subsystem sftp /usr/lib/openssh/sftp-server
Why wrong: Configures SFTP subsystem, not access control.
Question 184 of 1,000
XK0-005 Security Practice Question
This XK0-005 practice question tests your understanding of security. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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.
A security team wants to restrict SSH access to only users in the 'sshusers' group. Which configuration line in /etc/ssh/sshd_config achieves this?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
AllowGroups sshusers
Option B is correct because the `AllowGroups` directive in `/etc/ssh/sshd_config` restricts SSH login to users who are members of the specified group. By setting `AllowGroups sshusers`, only users in the 'sshusers' group are permitted to authenticate via SSH, meeting the security team's requirement.
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.
- ✗
DenyGroups sshusers
Why it's wrong here
Denies the group, opposite of what is needed.
- ✓
AllowGroups sshusers
Why this is correct
Allows only members of sshusers group.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
AllowUsers sshusers
Why it's wrong here
AllowUsers expects usernames, not groups.
- ✗
Subsystem sftp /usr/lib/openssh/sftp-server
Why it's wrong here
Configures SFTP subsystem, not access control.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is confusing `AllowGroups` with `AllowUsers`; candidates often select `AllowUsers sshusers` thinking it applies to a group, but it only matches a literal username, not group membership.
Detailed technical explanation
How to think about this question
The `AllowGroups` and `DenyGroups` directives in sshd_config are processed during the authentication phase, checking the user's supplementary group memberships via `getgrouplist()`. If multiple `AllowGroups` lines are present, only users in at least one of the listed groups are allowed; if both `AllowGroups` and `DenyGroups` are specified, `DenyGroups` is evaluated first. In real-world scenarios, this is commonly used to enforce least-privilege access for jump hosts or bastion servers, where only a specific admin group can SSH into critical systems.
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 security administrator must allow nursing staff to reach a patient records server while blocking access from the guest Wi-Fi VLAN. After applying an extended ACL, traffic is still blocked from nursing workstations. The ACL was applied outbound instead of inbound on the wrong interface. Questions like this test ACL direction and placement rules.
What to study next
Got this wrong? Here's your next step.
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FAQ
Questions learners often ask
What does this XK0-005 question test?
Security — This question tests Security — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: AllowGroups sshusers — Option B is correct because the `AllowGroups` directive in `/etc/ssh/sshd_config` restricts SSH login to users who are members of the specified group. By setting `AllowGroups sshusers`, only users in the 'sshusers' group are permitted to authenticate via SSH, meeting the security team's requirement.
What should I do if I get this XK0-005 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
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Last reviewed: Jul 4, 2026
This XK0-005 practice question is part of Courseiva's free CompTIA 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 XK0-005 exam.
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