Hello,
Do you know how to know the source course or activity from files and directories located in "temp/backup"?
Thank you so much.
Not sure I understand the question, but ...
There really shouldn't be anything in moodledata/temp/backup/ except 0 bytes .log files. If there is something like a long contenthash named directory, then cron/adhoc task clean up jobs may not have kicked in or there are issues with permissions to remove those folders/files.
If you are running a version of Moodle that has the feature, when a teacher/admin deletes a module in a course, a small backup is made of that module (actually has a .mbz filename extension) and is tagged as belonging to recyclebin.
One way to see those is via query of DB - mdl_files table ...
select id,contenthash,filename,filearea,filesize,userid from mdl_files where filename like '%.mbz'
Does that help?
'SoS', Ken