I host Crafty Controller (docker) on my desktop, because it is faster than my server. However, I’d like it for a MC server to be always running, so I don’t need to power on my desktop for anyone to join.
Minecraft runs fine on the server, as long as there aren’t many people on, and aren’t exploring new chunks. Generating new chunks is very cpu intensive, but one person exploring can be fine and is acceptable. However, I want a way to switch the same server to run on my desktop, nice and fast.
So basically, it of the time I want MC running on my server, and then when multiple people are playing (including me) I want to be able to turn off the server, and then turn it back on at my desktop.
I use NPM for my domain and SSL, however it’d be fine if people access at serverIP:port and desktopIP:port. That is acceptable (doesn’t need to be mc.example.com, but would be nice)
Would Syncthing be the tool to use? I could use it to sync the folder of Crafty to each computer…
Syncthing is entirely the wrong thing to use.
Anyway what you are describing is possible but it will take some work. I think it is likely not worth the effort. However, I’ll leave that up to you.
To do what you are describing you need to first have a way to send data back and forth between devices and then a way to shutdown and start containers.
To do this I would use Ansible. To start you are going to need to setup an Ansible service user on the server. Makes sure that it is configured so that it can run sudo without a password and is in the docker group. Once you have the service user you need to add it to the hosts file on your desktop.
Next, create two different playbooks. The first playbook will be the one that pulls the container over. First have it connect to the server and stop the container. Then have it run rsync to pull the data down to your local machine. Once the data is pulled have it start the container on your machine.
For the second playbook have it first stop the container on your desktop and then rsync the data over. Once the data is synced have it bring up the container on the server.
For safety you probably should add some check to make sure that you don’t mistakenly run the wrong playbook. You should add a check to make sure that the container is really running where it is expected. It is pretty easy to have Ansible run a check.
You technically could do this will pure scripting but I wouldn’t recommend it.
Ansible plugins:
https://docs.ansible.com/ansible/latest/collections/community/docker/docker_compose_module.html
https://docs.ansible.com/ansible/latest/collections/ansible/posix/synchronize_module.html
I’ve been wanting to start ansible, maybe this will push me over the edge