IIS Interview Questions and Answers
Freshers / Beginner level questions & answers
Ques 1. What is IIS?
Internet Information Services (IIS) is a web server software developed by Microsoft for hosting websites on the Windows operating system.
Ques 2. What is the purpose of the Metabase in IIS?
The Metabase is a hierarchical database that stores configuration settings for IIS. It includes information about websites, virtual directories, and server-wide settings.
Ques 3. What is the purpose of the Application Pool in IIS?
An Application Pool is a grouping of one or more websites that are served by a set of worker processes. It provides isolation between web applications to improve stability and security.
Ques 4. What is SSL and how can you configure it in IIS?
SSL (Secure Sockets Layer) is a protocol for secure communication over the internet. In IIS, SSL can be configured by obtaining and installing an SSL certificate, then binding it to a website.
Ques 5. Explain the purpose of the IIS Manager tool.
IIS Manager is a graphical user interface tool for configuring and managing IIS. It allows administrators to create, configure, and monitor websites and web applications.
Ques 6. What are the common authentication modes in IIS?
Common authentication modes in IIS include Windows Authentication, Forms Authentication, Basic Authentication, Digest Authentication, and Anonymous Authentication.
Ques 7. Explain the purpose of the IIS Compression module.
The IIS Compression module allows dynamic and static content to be compressed before being sent to the client, reducing bandwidth usage and improving website performance.
Intermediate / 1 to 5 years experienced level questions & answers
Ques 8. Explain the main components of IIS architecture.
IIS architecture consists of the HTTP.sys kernel mode driver, the user-mode components (inetinfo.exe and w3wp.exe), and the configuration and content stored in the Metabase.
Ques 9. How does the HTTP.sys kernel mode driver contribute to IIS?
HTTP.sys is responsible for processing HTTP requests and responses in kernel mode, providing improved performance and security for web applications hosted on IIS.
Ques 10. Explain the differences between a website and a virtual directory in IIS.
A website is a collection of content and settings that can be accessed using a unique domain or IP address. A virtual directory is a directory name that is mapped to a physical directory on the server and is part of a website.
Ques 11. Explain the significance of the Host Headers in IIS.
Host Headers allow a single IP address to serve multiple websites. The server uses the Host Header value in the HTTP request to determine which site to serve.
Ques 12. How can you troubleshoot a slow-performing website in IIS?
Troubleshooting steps may include checking server resource utilization, analyzing logs, optimizing code, reviewing database performance, and using tools like Performance Monitor.
Ques 13. Explain the process of securing an IIS server.
Securing IIS involves configuring server roles, enabling features like SSL, setting up authentication mechanisms, applying security patches, and implementing firewall rules.
Ques 14. What is the significance of the Global Assembly Cache (GAC) in IIS?
The GAC is a central repository for .NET assemblies shared by multiple applications. It allows these assemblies to be accessed by applications running on the same server.
Ques 15. How can you perform backup and restore of IIS configuration?
Backup and restore of IIS configuration can be done by using tools like AppCmd.exe, PowerShell scripts, or by manually exporting and importing configuration settings.
Ques 16. What is the purpose of the IIS Request Filtering module?
Request Filtering allows administrators to restrict the types of HTTP requests that are processed by IIS. It helps enhance security by blocking malicious requests.
Ques 17. What is the purpose of the IIS ARR (Application Request Routing) module?
ARR is a module that enables IIS to act as a load balancer. It can distribute incoming HTTP requests across multiple servers to achieve better performance and fault tolerance.
Ques 18. How can you monitor the performance of IIS?
Performance monitoring in IIS can be done using tools like Performance Monitor, IIS Manager, and third-party monitoring solutions. Key metrics include CPU usage, memory usage, and request/response times.
Ques 19. Explain the purpose of the IIS URL Rewrite module.
URL Rewrite allows administrators to define rules for rewriting or redirecting URLs. It is often used for search engine optimization (SEO) or to create user-friendly URLs.
Ques 20. What is FastCGI and how is it related to IIS?
FastCGI (Fast Common Gateway Interface) is a protocol for interfacing web servers with external applications. In IIS, FastCGI can be used to improve the performance of PHP and other non-native applications.
Ques 21. Explain the concept of Web Deploy in IIS.
Web Deploy is a tool for simplifying the deployment of web applications to IIS servers. It allows developers to package and deploy their applications with ease.
Ques 22. How can you optimize IIS for better performance?
Optimizing IIS involves configuring caching, enabling compression, tuning application pools, optimizing database queries, and minimizing the use of unnecessary modules.
Ques 23. What is the role of the IIS Health and Diagnostics module?
The Health and Diagnostics module in IIS provides monitoring and diagnostics features, including event logging, error tracking, and health monitoring of web applications.
Ques 24. How can you implement custom error pages in IIS?
Custom error pages in IIS can be implemented by configuring the
Ques 25. Explain the purpose of the IIS FTP server.
The IIS FTP server allows the transfer of files over the File Transfer Protocol (FTP). It provides features like user authentication, virtual directories, and SSL support for secure file transfers.
Ques 26. How can you configure SSL for a website in IIS?
SSL can be configured for a website in IIS by obtaining an SSL certificate, binding it to the website, and configuring the necessary SSL settings, such as protocol versions and cipher suites.
Ques 27. How can you configure IP-based restrictions in IIS?
IP-based restrictions in IIS can be configured by using the IP Address and Domain Restrictions feature in IIS Manager. This allows administrators to allow or deny access based on IP addresses or ranges.
Experienced / Expert level questions & answers
Ques 28. What is the role of ISAPI in IIS?
ISAPI (Internet Server Application Programming Interface) allows developers to extend the functionality of IIS by writing custom dynamic link libraries (DLLs) that can be loaded by IIS.
Ques 29. Explain the concept of Reverse Proxy in IIS.
A Reverse Proxy in IIS forwards client requests to another server, acting as an intermediary. It is often used for load balancing, caching, and enhancing security.
Ques 30. What is the purpose of the IIS WebSocket module?
The IIS WebSocket module enables full-duplex communication between a client and a server over a single, long-lived connection. It is commonly used in real-time web applications.
Most helpful rated by users:
- What is IIS?
- What is the purpose of the Metabase in IIS?
- What is SSL and how can you configure it in IIS?
- Explain the purpose of the IIS Manager tool.
- What are the common authentication modes in IIS?