Docker bind mounts always show /dev/mapper/ubuntu--vg-ubuntu--lv inside container instead of host path (Ubuntu LVM) [READ BODY]
I'm on Ubuntu Server using LVM (`/dev/mapper/ubuntu--vg-ubuntu--lv`).
Docker CE (not snap), rootful mode.
No matter what I do, bind mounts NEVER appear inside the container.
Example:
docker run -d \
--privileged \
-p 3000:3000 \
-v /home/luca/sorila/backend/tmp:/app/tmp \
-v /home/luca/sorila/backend/output:/app/output \
--name sorila-backend \
sorila-backend
docker inspect shows the mounts correctly:
"Mounts": [
{
"Type": "bind",
"Source": "/home/luca/sorila/backend/tmp",
"Destination": "/app/tmp"
}
]
But inside the container:
mount | grep app/tmp
ALWAYS shows:
/dev/mapper/ubuntu--vg-ubuntu--lv on /app/tmp type ext4
The host folder exists, permissions are 777, Dockerfile does NOT create /app/tmp, AppArmor disabled, privileged mode enabled, container recreated, image rebuilt, paths moved between /home and /srv — nothing changes.
Even with only ONE container running, the bind mount is ignored and the internal filesystem shadows it.
What could cause Docker to ignore bind mounts and always show the LVM root inside the container?