Hello friend,
Implementing load balancing can tremendously improve performance and availability of web-facing applications and services. Let‘s explore popular open source software options offering enterprise-grade load distribution for free.
Load balancers act as a reverse proxy, sitting in front of your application servers and distributing client requests across multiple backend hosts. This prevents overload on any single server.
Load balancers bring powerful benefits:
Scalability – Easily add backend hosts as traffic volumes grow
Resiliency – Route around failed servers, no downtime
Flexibility – Support different server locations, hardware
Performance – Handles caching, compression, TLS offload
Availability – Ensures apps stay accessible during spikes
There are three general categories of load balancers:
Hardware Load Balancers
Devices like F5, Citrix, A10 designed specifically for high speed traffic distribution and advanced networking capabilities. Can costs tens of thousands of dollars.
Cloud Load Balancers
Managed load balancing services from Amazon Web Services, Microsoft Azure, Google Cloud Platform and more. Fully managed, pay only for usage and capacity needed.
Software Load Balancers
Load balancer functionality implemented in software like HAProxy, NGINX, Traefik. Runs on commodity infrastructure allowing on-prem or cloud deployment.
Hardware load balancers are extremely performant but expensive. Cloud options are convenient but introduce cloud vendor dependencies. Software solutions offer greatest flexibility and customization as well as avoiding hardware costs.
Below we explore popular open source software load balancers powering real world applications at massive scale.
Seesaw – Designed by Google, Proven at Exabyte Scale
Seesaw was built internally by Google as a software load balancer to handle traffic for its servers and services. Key capabilities:
- Layer 4 load distribution supporting TCP and UDP traffic
- Horizontal scale by adding proxy nodes
- Anycast routing and Direct Server Return modes
- Sub-millisecond failover between nodes
- L4 connection tracking supporting millions of flows
Seesaw is deployed across thousands of Google front-end servers to create exabyte-scale load balancing fabrics. It also handles traffic for Wikimedia and Snapchat. For TCP traffic at massive scales, Seesaw is proven and unrivaled.
KEMP LoadMaster – Leader in Enterprise Application Delivery
The Kemp LoadMaster load balancer is offered as a free virtual appliance by KEMP Technologies, a recognized leader in application delivery technology per Gartner and Forrester Wave analyst reports.
The LoadMaster can replace expensive hardware from F5 and Citrix for complex application workloads. Capabilities include:
- Layer 4 TCP and Layer 7 HTTP load balancing
- Integrated web application firewall and DDoS protection
- TLS termination with SSL certificates
- Caching, compression, rate limiting features
- Pre-auth, SSO and APIs for microservices
- DevOps ready with CI/CD integration
KEMP claims 80% of Fortune 500 companies as customers, with the LoadMaster powering infra at Apple, GE, HP, Microsoft, Coca-Cola, FedEx, Tesco Bank and more. For the highest quality open source load balancer, Look no further.
HAProxy – Fastest Performance Across Benchmarks
HAProxy is the industry benchmark for load balancer performance, trusted by leading enterprises across all verticals:
| Stack Overflow | ||
| GitHub | Spotify |
Capabilities span:
- Layer 4 TCP and Layer 7 HTTP proxy
- Round robin, least connections distribution
- Health checks and fast session failover
- Real-time analytics dashboard
- Sticky sessions, SSL offloading
- 10Gbps+ throughput based on cores
Third party tests confirm HAProxy outperforms Nginx and hardware from F5. For blazing load balancing speed, look no further than HAProxy.
Zevenet – All-In-One Application Delivery Controller
Zevenet simplifies deliverying even complex, business-critical application architectures:
- L4 load balancing with health checks
- Full-featured L7 proxy, caching, WAF
- Zero-downtime high availability
- Historical analytics and monitoring
- Any orchestration environment
An Apache 2.0 licensed community edition is available as a virtual machine image or direct install on your own hardware. Zevenet offers an impressive breadth of capabilities for developers and reliability that enterprises demand.
Neutrino – Battle-Tested By Ebay at Scale
Built by Ebay, Neutrino is a distributed software load balancer proven in production for years across Ebay‘s infrastructure to handle peak loads of over 300,000 requests per second.
It is architected for:
- Horizontal scale through decentralized proxy nodes
- Sub-millisecond failover between proxies
- Flexible traffic routing rules
- Real-time analytics and metrics
Neutrino uses centralized controller nodes to program proxy configurations deployed across hundreds of hosts. For large distributed topologies, Neutrino offers proven scale and performance.
NGINX Plus – All-In-One App Delivery Platform
While open source NGINX provides basic load balancing, NGINX Plus offers an integrated, enterprise-grade solution:
- Layer 7 proxy, rules, redirection
- Session persistence, buffering
- Integrated Web Application Firewall
- Live activity monitoring
- Handles millions of concurrent connections
NGINX Plus can fully replace hardware balancers from Cisco, F5, Citrix matching their performance at a fraction of the cost based on independent tests.
Conclusion
I hope this overview helps provide deeper insight into open source load balancer options. Tools like HAProxy, NGINX, Seesaw and others match proprietary hardware in capabilities and performance.
Carefully consider your use case – L4 vs L7 needs, traffic volumes, high availability requirements when evaluating options. Reach out with any additional questions!
