When setting up a custom domain for MuleSoft applications hosted on CloudHub 1.0 using a Dedicated Load Balancer (DLB), follow these steps:

Set Up the TLS Certificate: Configure the DLB (acme-dib-prod) with a TLS certificate that covers the custom domain api.acmecorp.com. This certificate will allow HTTPS traffic to be securely directed through the DLB to your Mule applications.

DNS Configuration with CNAME:

Create a CNAME record that points api.acmecorp.com to the DLB hostname acme-dib-prod.lb.anypointdns.net.

The CNAME record enables the custom domain to resolve to the DLB provided by MuleSoft's Anypoint Platform. This CNAME mapping directs all traffic to the correct DLB for processing and load distribution.

Why Option B is Correct:

A CNAME record provides the necessary aliasing to acme-dib-prod.lb.anypointdns.net, which is the endpoint managed by Anypoint Platform for your DLB.

Option B also correctly identifies the need to configure the DLB with a TLS certificate specifically for api.acmecorp.com rather than for the DLB's internal hostname.

Explanation of Incorrect Options:

Options that suggest configuring the DLB with a TLS certificate for the DLB’s internal hostname or using an A record are not suitable in this scenario. MuleSoft CloudHub 1.0 DLBs work with CNAME records to provide flexible and scalable domain management, and a direct IP (A record) is not supported for these load balancers.

ReferencesFor more information on configuring custom domains and DLBs on CloudHub 1.0, refer to the MuleSoft documentation on DLB setup and DNS configuration​​.