I'm trying to use k3s as a replacement for minikube since there is a bug that spikes the CPU. The machine on which I'm deploying already has a docker-compose set of services bound to 443 and 80. k3s' traefik superceeds that bind and prevents my access to the existing services.
I want to move k3s' traefik to alternative ports. I've tried to stop traefik with sudo k3s server --no-deploy traefik but get Error: failed to create listener: failed to listen on 127.0.0.1:6444: listen tcp 127.0.0.1:6444: bind: address already in use
You did not stop the k3s service prior to running the sudo k3s server --no-deploy traefik command. This command simply starts a new server with the embedded traefik disabled. You'll have to stop the instance that was started before.
Using systemd, you'd stop the running instance using sudo systemctl stop k3s.
If you want to manually control when k3s is started, I'd recommend disabling the k3s service so that it doesn't get started automatically. To do so, run sudo systemctl disable k3s.
If you want k3s to still automatically start on boot up, edit the file at /etc/systemd/system/k3s.service and add the --no-deploy traefik option after the server command at the bottom of the file.