re-enabling ha-cluster renders the cluster unusable

[copiltembel]

Summary

I had a single-node microk8s cluster that was working fine (i.e. had some pods running as expected). I stupidly enabled ha-cluster add-on and now the cluster doesn't work anymore. I'd like to go back to the previous state of my cluster, not to lose the configuration, but that seems impossible now.

What Should Happen Instead?

Enabling ha-cluster should not render the cluster unusable.

Reproduction Steps

This is the easiest way to repro:

1. $ sudo snap install microk8s --classic
2. $ microk8s disable ha-cluster --force
3. $ microk8s enable ha-cluster

Now the (single-node) cluster is dead:

$ $ microk8s status
microk8s is not running. Use microk8s inspect for a deeper inspection.

$ microk8s inspect
Inspecting system
Inspecting Certificates
Inspecting services
  Service snap.microk8s.daemon-cluster-agent is running
  Service snap.microk8s.daemon-containerd is running
  Service snap.microk8s.daemon-kubelite is running
 FAIL:  Service snap.microk8s.daemon-flanneld is not running
For more details look at: sudo journalctl -u snap.microk8s.daemon-flanneld
  Service snap.microk8s.daemon-etcd is running
  Service snap.microk8s.daemon-apiserver-kicker is running
  Copy service arguments to the final report tarball
Inspecting AppArmor configuration
Gathering system information
  Copy processes list to the final report tarball
  Copy disk usage information to the final report tarball
  Copy memory usage information to the final report tarball
  Copy server uptime to the final report tarball
  Copy openSSL information to the final report tarball
  Copy snap list to the final report tarball
  Copy VM name (or none) to the final report tarball
  Copy current linux distribution to the final report tarball
  Copy asnycio usage and limits to the final report tarball
  Copy inotify max_user_instances and max_user_watches to the final report tarball
  Copy network configuration to the final report tarball
Inspecting kubernetes cluster
  Inspect kubernetes cluster

Building the report tarball
  Report tarball is at /var/snap/microk8s/6227/inspection-report-20240219_161304.tar.gz

Details:

Upon initial installation, ha-cluster is enabled:

$ microk8s status
microk8s is running
high-availability: no
  datastore master nodes: 127.0.0.1:19001
  datastore standby nodes: none
addons:
  enabled:
    dns                  # (core) CoreDNS
    ha-cluster           # (core) Configure high availability on the current node
...

My understanding is that ha-cluster needs at least 3 nodes, so it should not be enabled by default.
Or, if it is enabled by default, disabling and reenabling it without doing anything else should work fine.

Introspection Report

inspection-report-20240219_161304.tar.gz

[stale]

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