Custom domains in Supabase - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Custom Domain Setup in Supabase

Which of the following best describes the first step to configure a custom domain for your Supabase project?

A Add your custom domain in the Supabase dashboard and then update your DNS provider with the provided CNAME or A record.

B Directly update your DNS provider with your Supabase project URL without adding the domain in Supabase dashboard.

C Create a new Supabase project with the custom domain name as the project name.

D Configure SSL certificates manually on your local machine before adding the domain.

💡 Hint

Think about what needs to be done both in Supabase and your DNS provider to link your domain.

To use a custom domain, you must first add it in the Supabase dashboard. Supabase then provides DNS records you must add to your DNS provider to point your domain to Supabase.

❓ Configuration

intermediate

DNS Record Type for Custom Domain in Supabase

You want to point your custom domain app.example.com to your Supabase project. Which DNS record type should you use to correctly configure this?

A Create a TXT record with your Supabase project ID.

B Create an A record pointing <code>app.example.com</code> to <code>8.8.8.8</code>.

C Create a CNAME record pointing <code>app.example.com</code> to <code>project-ref.supabase.co</code>.

D Create an MX record pointing <code>app.example.com</code> to <code>mail.supabase.co</code>.

💡 Hint

Think about which DNS record type points a subdomain to another domain.

A CNAME record maps a subdomain to another domain name, which is required to point your custom domain to your Supabase project URL.

❓ Architecture

advanced

SSL Certificate Management for Custom Domains in Supabase

When you add a custom domain to your Supabase project, how is SSL (HTTPS) handled to secure your domain?

A You must manually upload your SSL certificate and private key in the Supabase dashboard.

B Supabase automatically provisions and renews SSL certificates for your custom domain using Let's Encrypt.

C SSL is not supported for custom domains; you must use HTTP only.

D You need to purchase an SSL certificate from a third party and configure it on your DNS provider.

💡 Hint

Consider how modern cloud services simplify HTTPS setup for custom domains.

Supabase uses Let's Encrypt to automatically create and renew SSL certificates for your custom domains, so you don't have to manage certificates manually.

❓ service_behavior

advanced

Behavior of Supabase Custom Domain After DNS Propagation Delay

After adding your custom domain and updating DNS records, you notice your domain is not immediately accessible. What is the expected behavior during this period?

A Your domain may not resolve or may show the old site until DNS changes propagate globally, which can take up to 48 hours.

B Your domain will instantly redirect to your Supabase project URL without delay.

C Supabase disables your project until DNS propagation completes.

D You must restart your Supabase project to activate the custom domain.

💡 Hint

Think about how DNS changes work on the internet.

DNS changes take time to spread across the internet. During this time, your domain may not resolve correctly or may show cached content until propagation finishes.

❓ security

expert

Security Best Practice for Custom Domain DNS Configuration in Supabase

Which DNS configuration practice enhances security when setting up a custom domain for your Supabase project?

A Share your DNS provider credentials with your development team for faster updates.

B Use a wildcard CNAME record pointing all subdomains to Supabase without restrictions.

C Disable HTTPS to avoid SSL certificate errors during setup.

D Use DNSSEC (Domain Name System Security Extensions) to protect your DNS records from tampering.

💡 Hint

Consider how to protect DNS records from being altered by attackers.

DNSSEC adds a layer of security by digitally signing DNS records, preventing attackers from redirecting your domain to malicious sites.