Load Balancers (Application, Network, Global) Questions and Answers for Viva

Answer-1: A load balancer is a system that distributes incoming network or application traffic across multiple servers to ensure no single server becomes overwhelmed.

Answer-2: The main types are Application Load Balancer (ALB), Network Load Balancer (NLB), and Global Load Balancer.

Answer-3: An ALB operates at the application layer (Layer 7) and routes traffic based on content such as URL, hostname, or headers.

Answer-4: A NLB works at the transport layer (Layer 4) and routes traffic based on IP protocol data.

Answer-5: A Global Load Balancer distributes traffic across servers in multiple geographic regions to improve latency and availability.

Answer-6: ALB operates on Layer 7 (Application Layer).

Answer-7: NLB operates on Layer 4 (Transport Layer).

Answer-8: It allows routing of requests to different targets based on the URL path of the request.

Answer-9: Host-based routing forwards requests based on the hostname in the HTTP header.

Answer-10: It is a feature that binds a user's session to a specific server, maintaining session state.

Answer-11: No, NLB passes the SSL traffic directly to the target server without termination.

Answer-12: It?s when the load balancer decrypts the SSL traffic before passing it to backend servers.

Answer-13: Application Load Balancer supports WebSocket connections.

Answer-14: Health checks monitor the health of backend instances and route traffic only to healthy ones.

Answer-15: ALB supports HTTP, HTTPS, and WebSocket.

Answer-16: NLB supports TCP, TLS, and UDP.

Answer-17: Cross-zone load balancing distributes traffic evenly across all registered targets in all availability zones.

Answer-18: Yes, it is enabled by default in ALB.

Answer-19: Target groups are used to route requests to one or more registered targets such as EC2 instances or containers.

Answer-20: A listener checks for connection requests using the protocol and port you configure.

Answer-21: They are usually charged per hour and per GB of data processed.

Answer-22: It directs traffic to the region with the lowest latency for the client.

Answer-23: Load balancers themselves don?t auto-scale, but they distribute traffic to auto-scaling backend instances.

Answer-24: It improves performance and reliability by routing users to the nearest healthy region.

Answer-25: A backend pool is a collection of IP addresses of virtual machines to receive the load-balanced traffic.

Answer-26: Rules define how traffic is distributed to backend pool instances.

Answer-27: Probes are used to determine the health of backend instances.

Answer-28: Internal load balancer routes traffic within a private network, while external LB handles public-facing traffic.

Answer-29: Autoscaling automatically adjusts the number of backend resources based on load; load balancers help manage the distribution.

Answer-30: It binds a user's IP address to a specific backend server to maintain session continuity.

Answer-31: Yes, especially Application Load Balancers can route based on content like URLs and headers.

Answer-32: It uses DNS responses to distribute traffic across multiple IP addresses or regions.

Answer-33: Traffic is redirected to a secondary region or endpoint when the primary becomes unhealthy.

Answer-34: It distributes traffic based on pre-assigned weights to backend servers.

Answer-35: A reverse proxy forwards client requests to backend servers and is commonly used in ALBs.

Answer-36: Round Robin, Least Connections, IP Hash, and Weighted Distribution.

Answer-37: Listener rules determine how requests are routed to target groups based on conditions like path or host.

Answer-38: Yes, NLB is designed to handle millions of requests per second with ultra-low latency.

Answer-39: NLB provides high performance for TCP and UDP traffic and is ideal for real-time applications.

Answer-40: Yes, ALB supports AWS Lambda as a target.

Answer-41: It distributes traffic equally across all backend servers in a cyclic order.

Answer-42: Geolocation routing sends user requests to resources based on their geographic location.

Answer-43: It defines the amount of time to wait for a response before considering the target unhealthy.

Answer-44: It?s the time a target remains registered after being marked unhealthy, to finish processing in-flight requests.

Answer-45: Yes, multiple listeners with different ports or protocols can be attached to a single ALB.

Answer-46: It routes traffic across multiple cloud regions for fault tolerance and performance.

Answer-47: Yes, NLB supports static IP and Elastic IP addresses.

Answer-48: It refers to removing unhealthy instances from the pool and redistributing traffic to healthy ones.

Answer-49: CloudWatch (AWS), Azure Monitor, and built-in dashboards provide metrics and logs.

Answer-50: It allows in-flight requests to complete before terminating the instance or deregistering it from the load balancer.