Heroku免费版应用自定义域名无法生效，Namecheap配置无误仍报错

Let’s walk through the most common fixes for your "nothing here yet" problem when using a Namecheap custom domain with your Heroku free app:

1. Verify Heroku Domain Configuration First #

First, make sure you’ve added both your root domain (robertosullivan.com) and subdomain (www.robertosullivan.com) to your Heroku app. Run this command in your terminal to check:

heroku domains --app robertosullivan

You should see both domains listed in the output. If either is missing, add it with these commands:

heroku domains:add robertosullivan.com --app robertosullivan
heroku domains:add www.robertosullivan.com --app robertosullivan

It’s easy to overlook adding one of them, and Heroku won’t route traffic to a domain that isn’t linked to your app.

2. Check DNS Propagation & Resolution #

Even if Namecheap confirms settings are correct, DNS changes can take up to 48 hours to fully propagate (though it’s usually faster). Test if your DNS is resolving properly with these terminal commands:

nslookup robertosullivan.com
nslookup www.robertosullivan.com

Both should return IP addresses associated with Heroku servers. If they don’t, try flushing your local DNS cache (steps vary by OS) or test from a different network to rule out local caching issues.

3. Confirm Your Heroku App Is Deployed & Running #

The "nothing here yet" message can also appear if your app hasn’t been successfully deployed to Heroku:

• First, verify your Heroku-provided free domain works (e.g., your-app-name.herokuapp.com). If that shows the same message, your issue is with deployment, not domain setup.
• Check your deployment logs for errors:

heroku logs --app robertosullivan --tail

Look for lines indicating a failed deploy or startup issues. Make sure you’ve pushed your code to Heroku with git push heroku main (or your default branch).

4. Double-Check Namecheap DNS Record Details #

• For your root domain (robertosullivan.com): Ensure the ALIAS/ANAME record uses @ as the host name (not robertosullivan.com itself). Namecheap uses @ to represent the root domain.
• For your www subdomain: Confirm the CNAME record has host name www and points exactly to concentric-cantaloupe-koaxxlt4rixetcdacu1ebggn.herokudns.com (no extra spaces or typos).

5. Rule Out HTTPS Issues (Free Heroku Limitation) #

Heroku’s free tier doesn’t support SSL for custom domains. If you’re trying to access https://robertosullivan.com, you’ll run into issues—stick to http://robertosullivan.com or http://www.robertosullivan.com for now.

Go through these steps one by one, and you should be able to pinpoint where the breakdown is. Most often, it’s either a missing domain entry in Heroku or DNS propagation delays.

内容的提问来源于stack exchange，提问作者Robert