Comment 2 for bug 1771342

Can you include the install.log from a system? Which curtin version is being used? The udev rules you show are from curtin 18.1-1 or less. In Bionic and Cosmic (18.1-5) where bcache dnames have been fixed to use uuid of the backing disk look like:

SUBSYSTEM=="block", ACTION=="add|change", ENV{CACHED_UUID}=="272a62c4-ed8f-4714-8909-78720ffad1e5", SYMLINK+="disk/by-dname/cached_array"