Simple Cloudflare tunnel with dynamic domain

Suppose that we want to publish localhost:3000

cloudflared tunnel --url http://localhost:3000

Cloudflare tunnel with fixed domain

1. Authenticate

cloudflared login

Then select domain from the browser prompt.

2. Create tunnel

cloudflared tunnel create <tunnel name>

tunnel name: The name of the service or group of services on your local machine

Example: foo-services = a tunnel for multiple projects

Example output:

cloudflared tunnel create foo-services

# Tunnel credentials written to ~/.cloudflared/61dbf6c3-a7e3-4d1b-80e4-15a1d90fd374.json.
# cloudflared chose this file based on where your origin certificate was found. Keep this file secret.
# To revoke these credentials, delete the tunnel.
# Created tunnel foo-services with id 61dbf6c3-a7e3-4d1b-80e4-15a1d90fd374

<tunnel uuid>.json → UUID required for config.yml

3. Update config.yml

Create/Update config.yml file

# use zed editor
zed ~/.cloudflared/config.yml

Add content to file:

Simple configuration (single domain):

url: http://localhost:3000
tunnel: <tunnel uuid>
credentials-file: ~/.cloudflared/<tunnel uuid>.json

Advanced configuration (multiple domains):

tunnel: 61dbf6c3-a7e3-4d1b-80e4-15a1d90fd374
credentials-file: ~/.cloudflared/61dbf6c3-a7e3-4d1b-80e4-15a1d90fd374.json
ingress:
  - hostname: sub-1.altrf.dev
    service: http://localhost:8100
  - hostname: sub-2.altrf.dev
    service: http://localhost:4321
  - service: http_status:404

Tunnel id 61dbf6c3... has multiple (domain → local service) mapping

⚠️ Important: The last row of ingress must be service: http_status:404

In the example file above, we map sub-1 public domain to django 8100 and sub-2 public domain to astro 4321.

4. Create domain mapping

cloudflared tunnel route dns <tunnel uuid or name> <host name>

You can create multiple domain mappings:

cloudflared tunnel route dns 61db... sub-1.yourdomain.com
cloudflared tunnel route dns 61db... sub-2.yourdomain.com

5. Start tunnel

cloudflared tunnel run <tunnel uuid/name>