30 network administrator interview questions to hire skilled professionals

Network administrators keep your organization’s networks running smoothly, ensuring that your IT infrastructure is functional, secure, and fast.  

Hiring the right person for this job can be as complex as the networks they will manage. However, if you use skills tests to evaluate candidates’ skills (such as cybersecurity and time management), along with the right network administrator interview questions, you can simplify your hiring process significantly. 

In this article, you’ll find our suggestions of skills tests you can use, along with 30 network administrator interview questions you can use when interviewing candidates for the role. 

We’ve also provided sample answers to some of them to help you evaluate applicants’ skills and experience, even if you have no network administration knowledge yourself.

How can you assess a candidate’s network administration skills?

To accurately evaluate a person’s proficiency in network administration, we advise you to use pre-employment skills testing and interviews. 

A skills-first approach to hiring helps you build an unbiased and objective recruitment process that results in better hires; in fact, 89% of employers see it as more effective in predicting on-job success than resumes.

Here are some of the pre-employment skills tests you could use when hiring a network administrator: 

• Microsoft SharePoint Administration: Assess candidates’ ability to configure lists and libraries and manage records within the SharePoint environment.

• Wireshark: Check whether candidates know how to use Wireshark for network analysis with this test. 

• Active directory: Make sure applicants know how to install, manage, and troubleshoot Active Directory. 

• Windows Server Administration: Evaluate candidates’ proficiency in deploying and operating Windows Server.

• Critical thinking: Analyzing issues critically is key for resolving them quickly and efficiently.

• Problem solving: Strong problem-solving skills are essential for any IT role.

• Communication: Network administrators need expert communication skills to work well with members of their team and coworkers from other departments.

• Motivation: Assessing applicants’ motivation is as important as evaluating their skills.

With TestGorilla, you can combine up to five skills tests in a single assessment; this will enable you to shortlist the best candidates from your talent pool quickly and efficiently. You can then invite them to an interview for a more detailed evaluation of their strengths and weaknesses.  To learn more about network administration skills, check out these 7 essential skills for network administrators.

Top 18 network administrator interview questions to assess applicants’ skills and knowledge

Below, you’ll find our selection of the best network administrator interview questions you can use during the recruitment process, along with sample answers to help you evaluate candidates’ responses. 

When assessing network administrators, look for applicants who are able to: 

• Answer all your questions confidently and with ease

• Simplify complex concepts and make them easy to understand

• Demonstrate their experience with specific examples 

• Learn new technologies and tools quickly

1. What motivated you to apply for the position of a network administrator at our company?

Candidate answer: 

I thrive in environments where I can tackle challenging issues and contribute to the growth of the network infrastructure. 

Your company has quickly built an excellent reputation and is on track to becoming a leader in your industry. The challenges that come with this growth are exciting to me and will enable me to not only apply my existing skills but also grow and learn.

Our advice: 

It’s important to assess candidates’ motivation during recruitment to make sure you hire a person whose expectations align with what your company can offer. A strong match will lead to better employee engagement and lower turnover.

One of the best ways to do this is by using TestGorilla’s Motivation test; during interviews, you can then follow up with more targeted questions like this one. 

2. What is DHCP? What are its main benefits? 

Candidate answer:

DHCP, short for Dynamic Host Configuration Protocol, is a network management protocol used to automate the distribution of IP addresses and other essential network configurations to devices on a network. 

So, when a device connects to the network, DHCP assigns it an IP address and other network configuration details like subnet mask and default gateway. 

This automation is crucial for efficiency, especially in dynamic network environments where devices frequently join and leave. By automatically assigning and managing IP addresses, DHCP eliminates the need for manual configuration and reduces the potential for errors.

3. What is the difference between a hub, a switch, and a router?

Candidate answer:

A hub, switch, and router are all integral parts of network infrastructure serving different purposes:

• Hubs are the simplest devices, acting like basic relays, broadcasting data to all other connected devices. They’re not very efficient for large networks and are also not particularly secure.

• Switches are more advanced; they direct data only to the specific devices it's intended for, which reduces unnecessary network traffic.

• Routers connect different networks together, for example when connecting an office network to the internet. Routers use IP addresses to determine the best path for forwarding data packets and come with additional features like firewall protection and wireless connectivity. 

4. How would you handle a network outage?

Candidate answer:

In an outage, I'd first check whether it's an isolated issue or a system-wide one. For widespread issues, my priority would be to restore connectivity to essential services and departments. 

I'd then work on systematically isolating the cause, which could be a hardware failure, a software issue, or an external factor. For this, I’d check:

• Physical connections

• Router/switch status

• Any recent changes to the network

In parallel, I'd make sure to keep all stakeholders in the loop and give them regular updates on my progress and the expected resolution time.

After fixing the issue, I’d focus on analyzing the root cause to protect the network against future outages.

5. What are the benefits of using VLANs in a network?

Candidate answer:

VLANs, or Virtual Local Area Networks, are great for segmenting a large network into smaller, manageable parts. VLANs are useful because they: 

• Improve network security by segmenting the network: This enables companies to isolate sensitive data and systems, which reduces the risk of unauthorized access

• Enhance performance by reducing broadcast traffic: Each department, group, or team can have their own network, built for their specific needs and traffic patterns

• Facilitate network configuration and management: Organizations can use VLANs to group users or devices with similar requirements or restrictions, which speeds up configuration and improves policy enforcement.

6. Can you explain the difference between HTTP, HTTPS, and FTP?

Candidate answer:

The differences between HTTP, HTTPS, and FTP are the following: 

• HTTP, short for  HyperText Transfer Protocol, is the standard protocol for transmitting web data; it’s not secure, which is why it’s systematically being replaced by HTTPS

• HTTPS is the secure version (S stands for Secure) of HTTPS, encrypting data for safe internet browsing

• FTP, or File Transfer Protocol, is used for transferring files between computers; it's therefore related to file management rather than to browsing web pages.

7. Can you explain the OSI model and its significance?

Candidate answer:

The OSI, or Open Systems Interconnection model, is a blueprint for understanding and designing networks and is crucial for troubleshooting and managing networks. Its seven layers are the following: 

• Physical layer

• Data-link layer

• Network layer

• Transport layer

• Session layer

• Presentation layer

• Application layer

These layers help pinpoint issues, ensuring that different network technologies can work together.

8. Describe a complex network problem you solved and how you approached it.

Candidate answer:

In a previous role, we faced an issue where network performance degraded significantly during peak hours. My team and I conducted a detailed analysis and discovered the problem was due to an overloaded server. 

We then developed a solution that involved load balancing and network segmentation, which fixed the immediate issue and also improved overall network efficiency. This challenge was a lesson in thinking outside the box and working together to solve a problem.

Our advice: 

Answers to this question will vary depending on candidates’ experience but skilled professionals should be able to demonstrate excellent problem-solving skills and, ideally, show that they’re also strong team players. 

9. How do you implement and manage network access controls?

Candidate answer:

Implementing access controls requires finding a balance between security and usability; my strategy involves a combination of hardware and software solutions to ensure robust network protection. 

I start by defining clear access policies based on roles and responsibilities within the organization. Then, I implement these policies using tools like firewalls and access control lists (ACLs) on routers and switches to manage who can access what. 

Regularly updating permissions, monitoring access logs, and educating users on security practices are part of my approach.

10. Can you tell us more about your experience with cloud-based networking?

Candidate answer:

I have lots of experience managing and optimizing cloud-based networks. 

In my last role, I led the migration of our on-premises network to a cloud-based solution. It involved careful planning, ensuring compatibility, and training the team on how to use the new environment. 

Within this project, I also implemented robust cloud security measures, including encryption and identity management protocols, to protect sensitive data.

11. Explain how you would design a network from scratch for a mid-sized company.

Candidate answer:

If I need to design a network from scratch, I’d first assess the company’s needs, such as:

• The number of users, data types, and applications

• Security requirements

• Expected growth 

I'd then plan for scalability and network protection from the outset, incorporating redundant pathways, backup solutions, and robust firewalls. I’d then look to implement user-friendly network management tools and create effective documentation to support the company’s network management in the long run. 

12. If you notice unusual network activity, what would you do? 

Candidate answer:

If I noticed unusual activity on a network I’m managing, I'd first isolate affected systems to contain potential issues. Then, I'd analyze traffic logs and real-time traffic to understand exactly what’s happening. 

I'd work with the security team to address any threats and restore normal operations.

Our advice: If you need to assess cybersecurity skills in more detail, you can use our Cybersecurity test to find applicants who are proficient in exploiting and mitigating vulnerabilities and threats related to networks, endpoints, and websites. 

13. How would you handle a situation where you had to implement a major change in the network infrastructure?

Candidate answer:

Any major change requires a solid plan and clear communication with all concerned parties.

I’d start with defining the objectives and business goals of the change. Then, I’d do a pilot test, gather feedback, and make adjustments as necessary. Training other employees, maintaining clear communication with everyone involved, and designing solid risk mitigation strategies are also crucial for a smooth transition. 

At the end, I’d conduct a review to assess whether the project was successful and identify areas for improvement.

14. What is your experience with different network monitoring tools?

Candidate answer:

I've worked with various network monitoring tools in the past, such as Nagios, SolarWinds, and Wireshark. I’m also very motivated to learn new technologies, depending on the role’s requirements. 

With Nagios, I've monitored network traffic and server performance, which was essential for maintaining system health. SolarWinds was my go-to for network performance monitoring and configuration management. 

Wireshark enabled me to analyze network protocols and diagnose traffic issues quickly and efficiently.

Our advice: 

Applicants’ responses will vary based on the tools they’ve used in the past; look out for those of them who aren’t afraid to upskill and learn to use new tools. 

You can use our Wireshark test to evaluate candidates’ proficiency with this application.

15. How do you ensure your data backup and recovery processes are effective?

Candidate answer:

My strategy involves first understanding the data's importance and also how often it’s updated, which helps me determine the backup frequency and the type of backup required. 

For critical systems, I implement real-time or near-real-time backups. I also ensure that backups are encrypted and stored securely, both on-site and off-site. 

Regular testing of the recovery process is essential to ensure that if data loss occurs, we can recover everything quickly. Additionally, I keep a close eye on backup logs and perform regular audits of our backup infrastructure to identify any potential issues. 

16. What are some common network performance issues and how do you troubleshoot them?

Candidate answer:

Common network performance issues I've encountered include:

• Bandwidth bottlenecks

• Configuration errors

• High latency

• Packet loss

To troubleshoot issues like those, I start with the basics, i.e. checking all physical connections and ensuring all hardware is functioning properly. I then use tools like ping and traceroute to diagnose latency or packet loss issues. 

For bandwidth bottlenecks, I analyze network traffic using a tool like Wireshark to identify which applications or devices are consuming excessive bandwidth. I also check for firmware updates and ensure that I’ve configured all network devices correctly.

17. How do you approach disaster recovery planning in a network environment?

Candidate answer:

When it comes to disaster recovery planning, I believe in a proactive and structured approach:  

1. First, I assess the potential risks, like natural disasters or cyber-attacks, and their impact on our network

2. Based on this, I develop a comprehensive plan that includes regular data backups, failover mechanisms, and clear recovery procedures

3. I also organize regular drills and training for the IT team, to make sure everyone knows their role in case of a disaster

18. Describe how you would handle a situation where you notice a coworker is violating the company’s IT policies.

Candidate answer:

If I noticed a coworker was violating IT policies, my first step would be to approach the situation with understanding and discretion. 

I'd have a casual, one-on-one conversation with them to discuss the issue. Maybe they're unaware of the policy or its importance, or maybe they don’t know how to actually implement it. I'd explain the potential risks and consequences of their actions for the company and for them.

If their behavior continued, or if it was a serious breach, I'd need to escalate it to my manager or the relevant department, but in a way that maintains the colleague's dignity and focuses on the issue, not the person.

Extra network administrator interview questions

If you need more ideas, here are 12 more questions you could ask network administrators to assess their skills:

1. Explain the process of subnetting and its advantages in network design.

2. Describe how a VPN works and name a few scenarios where it is commonly used.

3. How do you secure a network? Describe both physical and software measures.

4. What is the difference between IPv4 and IPv6, and what are the challenges in migrating from IPv4 to IPv6?

5. You need to integrate two networks with different protocols. What do you do?

6. How do you prioritize tasks when you need to address several critical issues?

7. A key piece of network hardware fails and the replacement's delivery will take a week. How do you handle this?

8. Describe a situation where you had to learn a new technology or skill to solve a job-related problem.

9. How do you implement QoS in a network, and what are the benefits?

10. Describe the benefits of using network automation tools.

11. How would you monitor and maintain a network with thousands of devices?

12. How do you ensure data integrity and confidentiality in a large-scale network?

For more ideas, check out our cybersecurity interview questions and IT interview questions.

Hire expert network administrators with the right interview questions

Finding the right person for the role of a network administrator is not an easy task, but if you have the right strategy and tools, you’ll be able to confidently hire the best candidate. 

Skills tests simplify the recruitment process because they enable you to identify the best talent from your candidate pool and zero in on the candidates who have the right skills for the job (and filter unqualified candidates). 

Interviews give you an opportunity to gain deeper insights into their experience, knowledge, and motivation to select the best match. 

Find your next network administrator with the help of TestGorilla. Sign up for a free demo  to talk to one of our experts – or try out our free plan to see for yourself why more than 10,000 companies have used TestGorilla to streamline recruitment.