`docker start host-agent` failed on unraid-1 with:
Error response from daemon: path / is mounted on / but it is not a
shared or slave mount
Unraid's root filesystem mount has "private" propagation by default and
rejects rslave from a container's volume spec. The static view of host
mounts (without rslave) is fine for an unraid box where the array is
mounted before host-agent starts — we lose the ability to see *future*
host mounts inside the container, which we never use anyway.
Container stays in Created state until this is fixed: user runs
install.sh + re-Applies my-host-agent template in Unraid UI.
matthew