Longhorn

This component is deployed to provide persistent storage replicated across the nodes in an easy fashion.

Current issues

As described in issue 7183 Longhorn v1.5.3 fails to recover from certain states for share-managers. The workaround was documented upstream.. Should be resolved in 1.6.x

volume-expansion is offline expansion only. This means you have to scale down deployments to expand volumes.
Adjusting the defaults in the helm deployment, doesn't adjust them in production. Production is managed with settings.longhorn.io objects which are basically a key-value CRD.
Longhorn requests by default 12% of your node CPUs for each instance-manager. This can easily exhaust your CPU resources in the cluster. Adjust this setting can only be done when all your volumes are detached, which implies scaling down all deployments that use volumes. (The deployment in this directory adjusted the CPU requests to 2%).
There are some opt-out telemetry settings since version 1.6.0.