I've been beating my head against the wall with this for a bit.  I'm running a LOT of docker containers on Unraid.  At work I implemented Rancher several years ago and have built a bunch of k8s clusters. 
I'm trying to spin up the single node, docker version of Rancher on Unraid and can't get it to function properly.  I can run the same container on my Windows box in WSL2 ubuntu linux without issue.

As far as I can tell there is something stopping Rancher from installing components during setup.  I can't tell if it is network related somehow or some other contributing factor.  I can see what is failing in the container logs but they aren't very helpful.
The Rancher container uses Docker in Docker to spin up a k3s cluster to run Rancher on.  It requires to be ran as root.  I have all of this configured correctly as far as I can tell.
I have plenty of disk space and RAM available.

I've wiped the Rancher data directory and started over with different configs several times.

I've tried using my own certs

The error is that it can't install Fleet, which is Rancher's gitops tool used to install other components.  No fleet means the rest of the internal setup fails.

Is there any special configuration with the Unraid version of Docker I don't know about?

 

I'm looking for any suggestions others might have as to what I could try to get this to work.

I've been running into many of the same pain points in trying to implement a performant/reliable Kubernetes cluster on my Unraid server without resorting to a VM. I think the move might be to migrate Unraid into a Proxmox VM imo. The other option I believe is opening 2375, but I feel like the security risks carried by this and the tunnel for the otherwise super useful MyServers plugin being open is a little too unsafe for my data. I think the template off of the community apps page currently fails to launch clusters/containers because of various containerd errors that point to the template being autogenerated, unsupported or at the very least not active enough for a stable homelab Kubernetes setup:

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