High Availability

High Availability (HA) of MetaMetrics® Services.


A. Each licensable API Service has an accompanying Service Level Agreement (SLA).

B. Some API Services and associated SLAs come with built-in high availability and redundancy endpoints which can be independently verified by customers in order to meet compliance standards.

C. HA commitments are service-specific and do not exceed SLA commitments. The purpose of HA is to ensure that we can deliver on our SLA commitments even when AWS suffers a regional outage.

D. HA and redundancy endpoints are periodically updated in this document. The regions in use are subject to change at any time.


MetaMetrics has implemented High Availability API services in AWS by using Route 53, latency-based routing, multiple AWS regions, per region API gateways, service health checking, and serverless Lambdas.

Customer requests sent to a global service endpoint are checked by Amazon’s Route 53 service, which uses latency-based routing to determine the best AWS region to process the customer request. The request is then directed to the API Gateway in the optimal region. There, API gateway and Lambda are used to create and manage the appropriate number of serverless instances to keep up with the current workload in that region.


Normally, customers configure their API client to point to our global endpoints. Customers may also temporarily test HA availability in each of the HA-capable API services to which they are subscribed. To do so, simply replace the global endpoint in your API client configuration with a regional endpoint. This will force traffic to the specified region. Once testing is complete, restore your API client configuration to use the global endpoint.

  • https://scoring-global.lexile.com
  • https://scoring-global-asia.lexile.com
  • https://scoring-global-west.lexile.com
  • https://scoring-global-east.lexile.com