Run Multiple Tunnels with a Single NGrok Agent

Recently, I've been developing a platform and trying to integrate a web api, web app, and Keycloak locally. Everything runs as expected via localhost, but when trying to create a docker compose file, things become a bit more complicated. The simple localhost addresses no longer work or redirect properly because each docker container is a separate host.

Normally, I use NGrok to help with these scenarios, but when trying to start a second ngrok tunnel, I received the following error:

ERROR:  authentication failed: Your account is limited to 1 simultaneous ngrok agent sessions.
ERROR:  You can run multiple simultaneous tunnels from a single agent session by defining the tunnels in your agent configuration file and starting them with the command `ngrok start --all`.
ERROR:  Read more about the agent configuration file: https://ngrok.com/docs/secure-tunnels/ngrok-agent/reference/config
ERROR:  You can view your current agent sessions in the dashboard:
ERROR:  https://dashboard.ngrok.com/agents
ERROR:  
ERROR:  ERR_NGROK_108
ERROR:  https://ngrok.com/docs/errors/err_ngrok_108
ERROR:  

After a bit of searching, I came across this on Stackoverflow showing how to update the configuration for multiple tunnels on a single agent.

# Find your ngrok config
ngrok config check

# Open your ngrok config
code /the/file/from/config/check.yml

# Update the configuration

version: "3"
agent:
  authtoken: xyz

tunnels:
  service_1:
    addr: 1234
    proto: http
  service_2:
    addr: 1235
    proto: http
  service_3:
    addr: 1236
    proto: http

# Start ngrok
ngrok start --all

This allowed me to authenticate with Keycloak via my api's swagger page, after updating the redirect url inside of the keycloak admin portal.