how load balancer works in azure

Load balancing is a critical component in modern application deployment. A load balancer is a device or software that distributes network or application traffic across multiple servers. In cloud computing, load balancing is essential to ensure scalability, performance, and high availability of applications. Azure Load Balancer is a software-defined load balancer that offers high throughput, high availability, and scalability to applications running on Azure.

Azure Load Balancer Architecture

Azure Load Balancer is a layer-4 (TCP and UDP) load balancer that distributes incoming traffic based on source IP address, destination IP address, and configured port. Azure Load Balancer is designed to handle traffic for Virtual Machines (VMs), Virtual Machine Scale Sets, and other Azure resources. The architecture of Azure Load Balancer consists of two main components—frontend and backend.The frontend component consists of a public IP address, a port, and a protocol (TCP or UDP) that clients use to access the service. The backend component consists of one or more virtual machines or virtual machine scale sets that host the application. Azure Load Balancer monitors the health of the backend instances and routes traffic to healthy instances.

Azure Load Balancer Types

Azure Load Balancer offers two types of load balancers—Basic Load Balancer and Standard Load Balancer. Basic Load Balancer is designed for traditional, non-cloud-native applications that require simple round-robin load balancing. It offers basic load balancing capabilities and does not support advanced features like health probes, session affinity, and outbound connections.Standard Load Balancer is designed for cloud-native applications that require advanced load balancing features. It offers a range of capabilities, including health probes, session affinity, outbound connectivity, and integration with virtual networks and Azure services. Standard Load Balancer also supports availability zones for high availability and multi-region deployments.

Benefits of Azure Load Balancer

Azure Load Balancer offers several benefits to applications running on Azure. Firstly, it provides high availability by distributing traffic across multiple instances of the application. If one instance fails, Azure Load Balancer redirects traffic to the remaining instances, ensuring seamless performance. Secondly, it improves the scalability and performance of applications by distributing traffic evenly across all instances. Thirdly, it provides security by hiding the internal IP addresses of the backend instances from the clients.

Conclusion

Azure Load Balancer is a critical component in modern application deployment. It offers high availability, scalability, and performance to applications running on Azure. With two types of load balancers and a range of capabilities, Azure Load Balancer provides a flexible and scalable load balancing solution for cloud-native applications. By choosing Azure Load Balancer, organizations can ensure the availability, scalability, and performance of their applications in the cloud.