Problem:

Given:

• Running coder on Kubernetes
• coder.securityContext.readOnlyRootFileSystem=true is set in Helm values
• coder.env contains { "name": "CODER_CACHE_DIRECTORY", "value": "/path/to/tmpfs" }
• coder.volumes specifies a writable volume not under /tmp

If you try running coder on Kubernetes with and set CODER_CACHE_DIRECTORY to /cache, pods will still fail with an error similar to:

create provisioner daemon: mkdir /tmp/provisionerdXXXXXXXXXXX: read-only file system

It appears that the built-in provisionerd server just writes to /tmp and this is non-configurable.
My expectation would be that the built-in provisionerd servers would honour CODER_CACHE_DIRECTORY.

Workaround:

Mount a writable volume on /tmp e.g.

coder:
  volumes:
  - name: "tmp"
    emptyDir: {}
  volumeMounts:
  - name: "tmp"
    mountPath "/tmp"
    readOnly: false