Frigate 0.16: Workaround for s6-overlay-suexec permissions issue on Docker with userns-remap + userns_mode: host

[kam821]

For anyone having trouble starting Frigate 0.16 container caused by the s6-overlay-suexec error on userns-remap enabled Docker with userns_mode: host set

s6-overlay-suexec: warning: real uid is 0 while effective uid is 165536; setting everything to 0; check s6-overlay-suexec permissions

/package/admin/s6-overlay/libexec/preinit: fatal: /run belongs to uid 165536 instead of 0, has insecure and/or unworkable permissions, and we're lacking the privileges to fix it.

s6-overlay-suexec: fatal: child failed with exit code 100

Here is a workaround:

Create an additional volume and mount it to the /run directory:

volumes:
  ...
  frigate_run:
    name: frigate_run

services:
  frigate:
  ...
    volumes:
      ...
      - frigate_run:/run

After the volume has been created, change the owner of the _data directory inside to root:root, e.g.:
chown -R root:root /var/lib/docker/165536.165536/volumes/frigate_run/_data

You can also try to directly mount bind some root owned, empty directory instead of creating volume.

It's not the most elegant solution, but it gets the job done.