Author : MD TAREQ HASSAN | Updated : 2021/04/18
What Is Load Balancing?
The term load balancing refers to the distribution of workloads across multiple computing resources. Load balancing aims to:
- Optimize resource use
- maximize throughput
- minimize response time
- avoid overloading any single resource
- etc.
Load Balancing can also improve availability by sharing a workload across redundant computing resources.
Load Balancing Services In Azure
- Azure Load Balancer
- Azure Traffic Manager
- Azure Application Gateway
- Azure Front Door
Azure Load Balancer
- Layer 4 load-balancing service (inbound and outbound, UDP and TCP protocols)
- Azure Load Balancer is zone-redundant, ensuring high availability across Availability Zones
Azure Traffic Manager
- A DNS-based traffic load balancer that enables you to distribute traffic optimally to services across global Azure regions
- It load balances only at the domain level. For that reason, it can’t fail over as quickly as Front Door (because of common challenges around DNS caching and systems not honoring DNS TTLs)
Azure Application Gateway
- A Layer-7, web traffic load balancer that enables you to manage traffic to your web applications
- See: Azure Application Gateway
Azure Front Door
- An application delivery network that provides global load balancing and site acceleration service for web applications
- Offers Layer 7 capabilities for your application like SSL offload, path-based routing, fast failover, caching, etc.
- Improves performance and high-availability of your applications
Comparison
Azure portal
- Go to: https://portal.azure.com/#blade/Microsoft_Azure_Network/LoadBalancingHubMenuBlade/overview
- Click ‘Service comparison’
When To Use Which Service?
- Traffic Manager:
- DNS based global routing
- Do not have requirements for Transport Layer Security (TLS) protocol termination
- Application-layer (per-HTTP/HTTPS request) processing
- Load Balancer:
- Network traffic load balancing
- Layer-4 load balancing
- Application Gateway:
- Layer-7 load balancing
- Application layer (OSI layer 7) load balancing
- Front Door:
- To optimize global routing of your web traffic
- Optimize top-tier end-user performance
- Reliability through quick global failover
Choose a load balancing solution
- Decision tree for load balancing in Azure: https://docs.microsoft.com/en-us/azure/architecture/guide/technology-choices/load-balancing-overview#decision-tree-for-load-balancing-in-azure
- Load balancing - help me choose : https://portal.azure.com/#blade/Microsoft_Azure_Network/LoadBalancingHubMenuBlade/overview