Overview
Describes the stages of the random load balancer algorithm used by the ULB to distribute incoming requests to backend servers.
The ULB distributes incoming requests to backend servers using the random load balancer algorithm. This approach is designed to minimize disruption when the backend server pool changes.
The algorithm ensures efficient request distribution and minimal impact during server pool changes.
Summary
Key components involved in this process include the ULB, backend servers, and the random load balancer algorithm.
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ULB: Receives client requests and manages distribution to backend servers.
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Backend servers: Handle the actual processing of client requests.
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Random load balancer algorithm: Maps incoming requests to backend servers using a hash-based lookup table.
The process ensures that incoming requests are efficiently mapped to backend servers, and that changes in the server pool result in minimal disruption to existing request mappings.
Workflow
These stages describe how the ULB distributes requests using the random load balancer algorithm.
- When a client request arrives, the ULB uses the random algorithm to determine the appropriate backend server.
- The client’s IP address (or another identifier) is used to generate a hash value.
- The hash value is mapped to a backend server using a precomputed lookup table.
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When the server pool...
Then...
And...
changes (addition/removal)
the algorithm recalculates the lookup table
only a small fraction of mappings are affected.
remains stable
the lookup table remains constant
traffic distribution continues without interruption.