What are Web EIPs? Why would my application need this feature?

For Cloud Platform Enterprise, Site Factory and Cloud Platform Professional subscribers, Acquia can provision an Elastic IP address (EIP) on the Cloud Classic application’s Drupal infrastructure when:

• The application must communicate to a remote service
• The service requires all sources of inbound connections to be allowlisted

In Cloud Next, outbound requests come from shared IPs. To allow auto-scaling and other resiliency measures, Acquia cannot assign specific servers to serve outbound requests for customer applications.

Web EIPs are designed to solve this problem. Application environments are assigned dedicated outbound proxies, and the proxies are assigned static IP addresses. Requests that originate from an application go through the proxies on their way out of the Acquia network, and you can allowlist the static IPs.