Global Load Balancer
Global Load Balancer (GLB) distributes traffic across servers in different locations to improve performance, reliability, and availability.
Definition
GLB uses DNS-based load distribution to direct users to available backend servers. It can improve response times, reduce downtime risk, and help maintain service continuity when a backend server becomes unavailable.
Features
| Feature | Description |
|---|---|
| Intelligent traffic distribution | Allocates web traffic across multiple servers based on location and server load. |
| Health monitoring and fault tolerance | Checks server health and reroutes traffic when a server fails. |
| Dynamic failback | Reintroduces a recovered server to traffic flow. |
| DNS-based load distribution | Uses DNS to balance traffic, including round-robin or other load distribution methods. |
| Cloud DNS integration | Requires the DNS zone to be hosted within SITE Cloud. |
Use Cases
- Distribute traffic for high-traffic websites and applications.
- Redirect traffic during server outages to support continuity.
- Direct users to nearby servers for geo-location-based content delivery.
- Balance traffic for enterprise-scale applications.
Prerequisites
- The DNS zone must be hosted within SITE Cloud.
Step-by-Step Guide
- Open Networking.
- Open Global Load Balancer.
- Click Create.
- Fill in the GLB settings.
- Click Submit.
| Field | Description |
|---|---|
| Member IP | The IP address of the server. |
| DNS Zone | The DNS zone used for GLB. |
| Load Balancing Method | The traffic distribution method. |
| Health Check Parameters | Health check settings for members. |
Note
Only public and shared IPs are supported in member health checks.
Managing a Global Load Balancer
- Open the GLB to view instance details.
- Click the edit button on the instance row to modify editable settings.
Warning
When editing a GLB instance, the Name, Zone, and Load Balancing Method cannot be edited.
Supported Health Check Types
Firewall rules are required for all health check IPs, regardless of health check type.
| Health check type | Notes |
|---|---|
| HTTP | Commonly used for web applications. |
| HTTPS | Commonly used for secure web applications. |
| TCP | Commonly used for non-HTTP services such as databases and custom applications. |
If one member is set to TCP, all health check members must use TCP. In that case, the path, health check IP, and port fields are disabled. The member IP is used as the health check IP, and all health check members use the same port as the first item in the active group.