TL;DR: Set the fallback origin Configure the fallback origin before the first customer: it answers for custom hostnames with no dedicated origin. # Workflow: SaaS customer domain onboarding ## 1. Verify it serves your app correctly for an unrecognized hostname. ## 2.

## Fix
1. Set the fallback origin Configure the fallback origin before the first customer: it answers for custom hostnames with no dedicated origin.
   Expected: this specific failure stops.
2. Verify it serves your app correctly for an unrecognized hostname. ## 2.
   Expected: the value or setting is exactly right, nothing ambiguous.
3. Customer adds the hostname Your onboarding flow calls the API (or the customer uses the dashboard) to add their hostname as a custom hostname on your zone. ## 3.
   Expected: this specific failure stops.
4. Set the apex expectation early Customers will ask for their root domain.
   Expected: this specific failure stops.
5. DNS forbids CNAME at the apex; supporting it needs the apex-proxying Enterprise add-on.
   Expected: this specific failure stops.

## Details
# Workflow: SaaS customer domain onboarding ## 1. Customer completes validation The customer proves domain control via DNS at their provider. Your system polls the hostname status until it is active; do not send the customer live until then. Tell customers this during sales, not during onboarding. ## 5. Operate Monitor per-hostname status continuously. Renewals and revalidation are your problem to track, not the customer's to remember. Keep the customer's CNAME target stable: changing it breaks every customer at once. ## Checklist - Fallback origin verified before customer one. - Validation status checked in code, with alerts. - Apex story documented for customers up front.

## When to use
You hit exactly this: Workflow: onboarding customer domains with Cloudflare for SaaS in Workflow.

## When not to use
A different error, or the same symptom in a different tool. This page only covers the failure above.

## Compatibility
Workflow.

## Edge cases
- Alert on hostnames that sit unvalidated: a customer who breaks their validation record later degrades silently. ## 4.