As new technologies change the face of business, they are also changing how business gets done. An increasing number of employees are working from home or on the road, which makes the job of the network administrator a critical one to ensuring the smooth flow of 
communication.
Job candidates in networking and computer systems should have a firm grasp of emerging network technologies, network processing, high-performance computing, network programming, and security issues.
Sampling of possible interview questions for network and computer systems administrator positions:
What types of networks have you worked with?
Explain the benefits of subnetting.
What is the worst network outage situation you have faced? What was your role in restoring services?
What are some of the daily security issues faced by network administrators?
If a systems crash happens after hours, are you OK with coming in and staying until the job is done to fix it?
Have you ever worked with company expansion and mapping new networks?
What are the three major types of networks?
How would you go about implementing a new network? What hardware items would you need? What software?
Explain how traceroute works.
What are the steps you take if the internet suddenly stops working for either one user or a whole department?
Employee A calls and asks for a file from employee B’s personal network share. Employee B is out sick that day. Employee A says the file is critical for an important meeting which is happening in 20 minutes. What do you do?
What was the worst issue you’ve ever caused and how did you fix it?
Pick two of these to describe in detail: IPSEC, OSPF, IPv6, TCP, HTTP, VRRP, STP, anycast.
How do you ensure all of your equipment and software is current?
A user is unable to ping a system on the network. How can wireshark be used to solve the problem?
What certifications do you have? If none, why not?
What is your experience supporting mobile workers?
What is the difference between a workgroup and a domain?
How does the network administrator and networking team affect the other areas of the IT department?
How do you make sure the basic LAN infrastructure is secure from outside attacks?
The business office is unable to process checks because the server just went down. At the same time, the CEO calls and is having a meltdown because his laptop is not working. What do you do?
What are the requirements for a strong password?
What is the difference between a print server and a network attached printer?
Describe your experience with WAN connectivity.
Discuss your experience with strategic planning for the information systems of a company.