Single-AZ Load Balancer Check

Rule Details

**Table 1** Rule details
Parameter	Description
Rule Name	elb-multiple-az-check
Identifier	Single-AZ Load Balancer Check
Description	If a load balancer is mapped to fewer than two AZs, this load balancer is non-compliant.
Tag	elb
Trigger Type	Configuration change
Filter Type	elb.loadbalancers
Rule Parameters	None

Application Scenarios

A dedicated load balancer works in multiple AZs. Load balancers in different AZs work in active-active or multi-active mode. They allocate client access requests to the nearest instances in the same AZ as the client. They can also prevent service interruptions by allocating requests among AZs. For details, see the Dedicated Load Balancer Overview.

Solution

Configure multiple AZs when you buy a load balancer. If an existing load balancer is deployed in only one AZ, call the API for Deploying a Load Balancer in Other AZs.

Rule Logic

If an ELB load balancer is deployed in multiple AZs, this load balancer is compliant.
If an ELB load balancer is deployed in only one AZ, this load balancer is non-compliant.

Parent topic: Elastic Load Balance

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