Interview Questions and Answers

Internet Information Services (IIS) is a web server software developed by Microsoft for hosting websites on the Windows operating system.

The Metabase is a hierarchical database that stores configuration settings for IIS. It includes information about websites, virtual directories, and server-wide settings.

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.

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.

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.

Common authentication modes in IIS include Windows Authentication, Forms Authentication, Basic Authentication, Digest Authentication, and Anonymous Authentication.

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.

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.

HTTP.sys is responsible for processing HTTP requests and responses in kernel mode, providing improved performance and security for web applications hosted on 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.

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.

Troubleshooting steps may include checking server resource utilization, analyzing logs, optimizing code, reviewing database performance, and using tools like Performance Monitor.

Securing IIS involves configuring server roles, enabling features like SSL, setting up authentication mechanisms, applying security patches, and implementing firewall rules.

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.

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.

Request Filtering allows administrators to restrict the types of HTTP requests that are processed by IIS. It helps enhance security by blocking malicious requests.

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.

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.

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.

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.

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.

Optimizing IIS involves configuring caching, enabling compression, tuning application pools, optimizing database queries, and minimizing the use of unnecessary modules.

The Health and Diagnostics module in IIS provides monitoring and diagnostics features, including event logging, error tracking, and health monitoring of web applications.

Custom error pages in IIS can be implemented by configuring the element in the web.config file or by using the IIS Manager to set up custom error pages for specific HTTP status codes.

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.

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.

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.

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.

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.

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.