Final answer:
To verify a custom domain on an App Service, add a TXT record for domain verification and a CNAME or A record to point the domain to the service. After updating DNS settings, wait for propagation before completing the verification.
Step-by-step explanation:
To verify a custom domain on an App Service, you typically need to add specific DNS records to your domain's DNS settings. The specific records required are a TXT record for domain verification and a CNAME record or an A record (for root domains) to point your domain to the App Service.
The TXT record is used to confirm ownership of the domain, and usually, you have to add a unique verification ID provided by the App Service in this record. The CNAME or A record is then used to direct traffic to your App Service.
After updating these records in your DNS management interface, it's essential to wait for them to propagate, which can take up to 48 hours.
Once propagation is complete, you can finalize the verification process on the App Service platform. Remember to always follow the specific instructions provided by your App Service provider as procedures can slightly vary between platforms.