Welcome to the IIS Interview Questions and Answers Page

Get ready to ace your IIS interview with our comprehensive collection of questions and expertly crafted answers. Whether you’re a beginner or an experienced professional, this resource will help you enhance your knowledge and confidently tackle any IIS-related interview. Good luck!

Top 20 Basic IIS interview questions and answers

1. What is IIS?
IIS stands for Internet Information Services. It is a web server software package developed by Microsoft for hosting websites and web applications on Windows servers.

2. What are the different types of IIS authentication?
IIS supports several authentication methods, including Anonymous, Basic, Digest, Windows, and Client Certificate.

3. What are application pools in IIS?
Application pools in IIS are used to isolate web applications from one another. Each application pool runs as a separate process and can be assigned different configurations and security settings.

4. How do you configure SSL in IIS?
To configure SSL in IIS, you need to install a SSL certificate on the server and then bind it to the website or application hosted in IIS. This can be done through the IIS Manager.

5. What is the purpose of the IIS metabase?
The IIS metabase is a configuration store for IIS settings. It stores information about websites, virtual directories, application pools, and other IIS components.

6. What is the difference between IIS and Apache?
IIS and Apache are both web server software, but they have different architectures and run on different operating systems. IIS is developed by Microsoft and primarily runs on Windows servers, while Apache is open-source and runs on various operating systems, including Windows, Linux, and macOS.

7. How can you monitor IIS performance?
IIS provides several performance monitoring tools, such as Performance Monitor and Log Parser, which can be used to monitor various performance counters, log files, and other metrics.

8. How do you troubleshoot IIS errors?
Troubleshooting IIS errors involves analyzing log files, checking event logs, and examining server configurations. Tools like Failed Request Tracing and Debug Diagnostics can also be used to identify and resolve issues.

9. What is the difference between a website and a virtual directory in IIS?
A website in IIS represents a collection of web pages and other content that can be accessed through a domain or IP address, while a virtual directory is a directory within a website that can be mapped to a different physical directory on the server.

10. How can you optimize IIS performance?
To optimize IIS performance, you can fine-tune various settings such as caching, compression, and connection limits. You can also configure IIS to use a reverse proxy server or load balancing for improved scalability.

11. What is the purpose of the IIS Manager?
The IIS Manager is a graphical tool provided by Microsoft for managing and configuring IIS. It allows administrators to control various aspects of IIS, such as websites, application pools, SSL certificates, and security settings.

12. How do you secure an IIS server?
To secure an IIS server, you can implement various measures such as configuring strong authentication methods, using SSL/TLS encryption, restricting access through IP filtering or firewall rules, and regularly applying security patches and updates.

13. What is the difference between a wildcard SSL certificate and a single domain SSL certificate?
A wildcard SSL certificate can secure multiple subdomains of a domain, while a single domain SSL certificate only secures a single domain name and any subdomains must be secured with separate certificates.

14. How can you redirect HTTP traffic to HTTPS in IIS?
You can redirect HTTP traffic to HTTPS in IIS by configuring URL Rewrite rules or by using the HTTP to HTTPS redirection feature available in IIS versions 7.0 and above.

15. What is the purpose of the Global.asax file in an IIS application?
The Global.asax file is an optional file in an IIS application that contains event handler methods for application-level events, such as Application_Start, Application_End, Session_Start, and Session_End.

16. How can you configure IIS to use a custom error page?
You can configure IIS to use a custom error page by specifying the URL or file path of the error page in the web.config file of the website or application.

17. What is the maximum file size that can be uploaded to an IIS server?
The maximum file size that can be uploaded to an IIS server is determined by various configuration settings, such as the maxAllowedContentLength property in the web.config file, the requestLimits property in the applicationHost.config file, and the maximum allowed file size set in the IIS Manager.

18. How can you restrict access to a specific directory in IIS?
You can restrict access to a specific directory in IIS by configuring authentication and authorization settings for that directory. This can be done through the IIS Manager or by modifying the web.config file.

19. What is an ISAPI extension in IIS?
An ISAPI extension in IIS is a DLL (Dynamic Link Library) that extends the functionality of IIS by intercepting and processing incoming HTTP requests. ISAPI extensions can be used to add custom processing or functionality to an IIS server.

20. How can you backup and restore IIS configurations?
You can backup and restore IIS configurations by using the IIS Manager’s backup and restore features, or by manually exporting and importing specific settings using tools like AppCmd.exe or PowerShell commands.

Top 20 Advanced IIS interview questions and answers

1. What is IIS?
IIS stands for Internet Information Services. It is a web server software package designed by Microsoft for hosting websites, applications, and services on Windows-based servers.

2. What are the different versions of IIS?
The different versions of IIS include IIS 5.0, IIS 6.0, IIS 7.0, IIS 7.5, IIS 8.0, IIS 8.5, and IIS 10.0.

3. What is the application pool in IIS?
An application pool is a worker process (w3wp.exe) that runs applications within IIS. It provides isolation and ensures that errors or issues in one application do not affect others.

4. What is the role of the HTTP.sys in IIS?
HTTP.sys is a kernel-mode driver responsible for processing HTTP requests and responses in IIS. It acts as an intermediary between the incoming HTTP request and IIS worker process.

5. What is a virtual directory?
A virtual directory is a named location in an IIS web server that points to a physical directory on the server’s file system. It allows the content to be served from a different location without having to create a new website.

6. Explain the different authentication modes in IIS.
IIS supports various authentication modes, including Basic, Digest, Windows, Forms, and Anonymous. Basic authentication sends the username and password in plain text, while Windows authentication uses the Windows user account for authentication.

7. How can you optimize IIS performance?
To optimize IIS performance, you can implement caching, enable compression of static content, limit the use of server-side scripts, optimize database queries, and use a content delivery network (CDN).

8. What is the purpose of the IIS metabase?
The IIS metabase is a repository that stores configuration information for IIS. It contains information about websites, applications, virtual directories, and other server-related settings.

9. What is the difference between IIS and Apache?
IIS is a web server developed by Microsoft and primarily used on Windows servers, while Apache is an open-source web server software that runs on various operating systems, including Windows, Linux, and macOS.

10. How can you troubleshoot IIS-related issues?
To troubleshoot IIS-related issues, you can check event logs, verify server configurations, monitor performance counters, use IIS Manager, review HTTP error codes, and analyze server logs.

11. What is the purpose of the IIS request pipeline?
The IIS request pipeline handles incoming HTTP requests and processes them through a series of modules and components. It processes the request, executes the necessary handlers, and generates the appropriate response.

12. Explain the difference between a web garden and a web farm.
A web garden refers to a configuration where multiple worker processes (application pools) run on a single server, allowing parallel processing. On the other hand, a web farm refers to a configuration where multiple servers are used to host a website or application, providing load balancing and high availability.

13. What is the purpose of the IIS Rewrite module?
The IIS Rewrite module is used to rewrite URL paths and redirect requests based on pattern matching rules. It is helpful in creating SEO-friendly URLs or redirecting specific requests to different pages.

14.How can you configure SSL/TLS on IIS?
To configure SSL/TLS on IIS, you need to obtain an SSL certificate for your domain, install it on the server, and bind it to the appropriate website. You can also configure SSL settings and enable HTTPS redirection in the IIS configuration.

15. What is the purpose of the IIS compression feature?
The IIS compression feature allows the server to compress static content before sending it to the client. This reduces the size of the data transfer, resulting in faster page loading times and reduced bandwidth usage.

16. Explain the concept of authentication delegation in IIS.
Authentication delegation allows IIS to delegate user authentication to another server or service. This is useful when a client application needs to access multiple resources that require different authentication mechanisms.

17. How can you configure URL rewriting in IIS?
URL rewriting can be configured in IIS using the IIS Rewrite module. You can create rewrite rules based on regular expressions or predefined patterns, redirect URLs, or modify query strings.

18. What is the default port number for IIS?
The default port number for IIS is 80 for HTTP and 443 for HTTPS (SSL/TLS).

19. How can you enable and configure logging in IIS?
Logging in IIS can be enabled and configured through the IIS Manager. You can specify the log file format, log file location, fields to be logged, and other settings for both the W3C format and NCSA format logs.

20. What is the purpose of the IIS FTP service?
The IIS FTP service allows users to upload, download, and manage files on an FTP server. It provides a secure and efficient way of transferring files over the Internet.

Interview Questions and answers

Filter:AllUnanswered
Explain the main differences between IIS and Apache web servers.
suresh answered 4 months ago • 
56 views1 answers0 votes
Can you explain the difference between IIS authentication modes?
suresh answered 4 months ago • 
58 views1 answers0 votes
How can you troubleshoot and diagnose performance issues in IIS?
suresh answered 6 months ago • 
94 views1 answers0 votes
What is the main difference between IIS and Apache web server?
suresh answered 6 months ago • 
67 views1 answers0 votes
How do you troubleshoot performance issues in IIS?
suresh answered 6 months ago • 
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Can you explain the difference between Classic ASP and ASP.NET in IIS?
suresh answered 6 months ago • 
273 views1 answers0 votes
What is the difference between IIS and Apache web servers?
suresh answered 6 months ago • 
77 views1 answers0 votes
What are the various authentication modes supported by IIS?
suresh answered 6 months ago • 
65 views1 answers0 votes