dockerPreloader fails due to "read-only file system" error #74143
Description
Attempting to use the virtualisation.dockerPreloader feature on current master (6e38def) fails to start containers on the preloaded images. The existing test in nix-build nixos/tests/docker-preloader.nix reproduces the error.
Log message from running the tests on hydra:
docker# [ 12.601197] dockerd[747]: time="2019-11-24T18:47:45.973722725Z" level=error msg="Handler for POST /v1.40/containers/create returned error: open /var/lib/docker/overlay2/bcc596043c9e8253025a4cfae4a12eafd168c13342898e60345669e7b453225f/committed: read-only file system"
docker# /nix/store/rbhcr27bx53hqwx72rjkgbj5pfn7jix3-docker-19.03.4/libexec/docker/docker: Error response from daemon: open /var/lib/docker/overlay2/bcc596043c9e8253025a4cfae4a12eafd168c13342898e60345669e7b453225f/committed: read-only file system.
Looking at recent builds, it looks like it's been failing consistently for a while.
cc @nlewo as the author of the module
Maintainer information:
module:
- virtualisation/docker-preloader.nix