Configuring Load Balancer Listener Rules

Intelligent Traffic Steering with Listener Rules

Backpac’s Load Balancer Listener Rules enable you to route incoming traffic efficiently based on various criteria, including HTTP headers, RPC methods, and source IPs. These customizable routing rules help optimize performance, scalability, and reliability for your blockchain applications.

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How to Configure a Listener Rule in Backpac

Step 1: Log in to Your Backpac Dashboard

To begin, log in to your Backpac dashboard and navigate to the Load Balancer section.

Step 2: Create a Listener Rule

Click on the Create Listener Rule button to start the configuration process.

Step 3: Configure the Rule Options

You’ll need to provide the following details to define your Listener Rule:

1. Name:

   • Give your rule a descriptive name (e.g., Ethereum-Method-Rule) to easily identify it later.

2. Priority:

   • Assign a priority to the rule. The higher the number, the lower the priority. Rules with higher priorities are evaluated first, so make sure the order of evaluation matches your needs.

3. Conditions:

   • Specify the conditions under which this rule will apply:
     • RPC Methods: Choose the specific RPC methods to trigger this rule.
     • HTTP Headers: Define custom HTTP header values that should match for routing.
     • Source IPs: If needed, specify IP address ranges that should trigger the rule.

4. Target Group:

   • Select the Target Group where the traffic should be forwarded. Target Groups consist of a set of RPC nodes or endpoints responsible for handling requests.

Step 4: Save the Listener Rule

Once you’ve filled in the configuration details, click Save to finalize your rule.

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Example: Configuring a Listener Rule for Ethereum Methods

Scenario

You want to route two different Ethereum RPC methods to two separate target groups for optimized handling:

• eth_getBlockByNumber: This method requires the highest available block height and should be directed to the target group containing the most up-to-date Ethereum node.
• eth_getLogs: This method can be routed to any available Ethereum node, as it doesn’t require the latest block data.

Steps to Configure:

1. Create Listener Rules:

   • Rule 1: Matches requests for the eth_getBlockByNumber RPC method and forwards traffic to the Ethereum Target Group that contains the node with the highest block height.
   • Rule 2: Matches requests for the eth_getLogs RPC method and forwards traffic to any available Ethereum Target Group.

2. Set Rule Priorities:

   • Set Rule 1 to a higher priority than Rule 2 to ensure that it is evaluated first.

3. Assign Listener Rule:

   • Attach the listener rule to the appropriate blockchain network for which the rules apply.

Expected Result:

• Requests for eth_getBlockByNumber are directed to the Ethereum Target Group with the highest block height.
• Requests for eth_getLogs are distributed across available Ethereum RPC nodes.

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Listener Rule Features

Custom Routing Conditions

Listener Rules allow for flexible routing based on the following criteria:

• RPC Method Matching: Routes traffic to different backend services based on the RPC method.
• HTTP Header Matching: Routes traffic based on specific header values (ideal for handling API versioning or authentication tokens).
• Source IP Routing: Routes traffic from specific IP addresses or IP ranges to dedicated Target Groups for specialized handling.

Priority-Based Matching

• Rule Prioritization: Rules are evaluated in order of priority. Lower priority numbers indicate higher priority, meaning the rules are checked from highest to lowest priority.
• Precedence: Ensure that more specific rules are placed higher in the list to take precedence over more general rules.

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Benefits of Configuring Listener Rules

• Optimized Traffic Flow: You can route traffic to the most appropriate service based on the request's characteristics (e.g., method, header, or source IP).
• Scalability: Scale your infrastructure efficiently by distributing traffic according to specific needs, such as routing traffic for high-load RPC methods to specialized nodes.
• Customization: Tailor your traffic management based on the unique requirements of your blockchain application.
• Reliability: Ensure that requests are routed to healthy, responsive endpoints, improving overall system reliability and minimizing downtime.

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Conclusion

Configuring Load Balancer Listener Rules in Backpac provides a robust way to manage incoming traffic and optimize the performance of your blockchain applications. By defining conditions like RPC methods, HTTP headers, and source IPs, and selecting appropriate Target Groups, you can create a flexible and scalable routing system that meets your application's needs.

For more information on creating Listener Rules, refer to the full Backpac Load Balancer documentation.