Treafik v2 example

[dirrgang]

Hello everyone,

for my own use I modified the example provided by this repository for use in my own Traefik2 setup. I figured others might find this useful too, so I modified my example back to something more "reusable".

This is my first pull request to a bigger project, so please excuse me if I'm stepping on someone's toes or doing something wrong.

I suppose this example is a little more elaborate than is normal because of the creation of specific "frontend/backend" networks and such. Theoretically that could be cut down too. Other things that are different:

• Uses DNS verification for Let's Encrypt certificate creation.
• Removed passwordless root login to the mariadb container (why was/is that a thing?)
• Reused chains/services from my traefik setup which in theory could be removed also. I didn't want to gut too many things in fear of breaking something.
• Updated the docker-compose syntax somewhat, at least using the more extensive method for volumes.
• Modified the folder structure to clearly separate librenms and traefik data, which also allows for easier extension when adding more containers. Again, perhaps not necessary for a basic example, but I figured it can also be removed if it's deemed overkill.
• Moved some of the environment variables into separate .env files.
• Added some comments to the docker-compose file.

I'd be happy to make further modifications if there's something not to your liking, but I figured this is a good place to start.

[CLAassistant]

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[crazy-max]

@dirrgang

for my own use I modified the example provided by this repository for use in my own Traefik2 setup. I figured others might find this useful too, so I modified my example back to something more "reusable".

I prefer to keep our example as simple as possible. For example many users cannot handle DNS challenge, that's why we use the HTTP challenge here. But thanks for your input! I suggest you rather post your stack on our community forum, I'm sure some users will be interested in it.

Btw I've updated our example for version 2 of Traefik if you want to take a look.

Thanks again and sorry for the delay.