You have copied a new .ko module into /lib/modules/$(uname -r)/extra/ and modprobe still reports that the module is not found. Type the command, run as root, that rebuilds the module dependency database (modules.dep and its map files) for the running kernel.
LPIC-1 Exam 101-500, objective 101. System architecture easy
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Answer
Type the answer.
Accepted answers
depmoddepmod -adepmod --all/sbin/depmod/usr/sbin/depmod
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
modprobe never scans the module tree at run time; it reads the index that depmod writes, chiefly /lib/modules/<version>/modules.dep and modules.dep.bin, plus the alias maps. A module that exists on disk but is absent from that index is invisible to modprobe. depmod with no arguments processes the running kernel's directory; depmod <version> targets another installed kernel. Package managers run it automatically when they install a kernel or a module package, which is why the step is only noticed when files are copied in by hand.
Where this comes from
- Cited
- manual page depmod(8)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 101 and space the ones you get wrong.
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