insmod VS modprobe

`modprobe` and `insmod` are both commands used in Linux for managing kernel modules, but they have some key differences in terms of functionality and usage.

1. Purpose:
   - `modprobe`: The `modprobe` command is used to automatically load modules and their dependencies, based on the module names specified. It resolves dependencies and loads any required modules before loading the specified module.
   - `insmod`: The `insmod` command is used to manually insert a single module into the Linux kernel. It does not resolve dependencies or load any required modules automatically.

2. Dependency Handling:
   - `modprobe`: When you use `modprobe` to load a module, it automatically resolves and loads any dependencies required by that module. It checks the module dependencies specified in the module configuration files and loads them in the correct order.
   - `insmod`: The `insmod` command does not handle dependency resolution. If a module has dependencies, you need to ensure that the required modules are loaded manually before using `insmod` to insert the module.

3. Configuration Files:
   - `modprobe`: `modprobe` reads the module configuration files located in the `/etc/modprobe.d/` directory. These configuration files can specify options, aliases, and other settings related to module loading and behavior.
   - `insmod`: `insmod` does not read any configuration files. It only inserts the specified module into the kernel without any additional settings.

4. Module Search Paths:
   - `modprobe`: `modprobe` searches for modules in the standard module directories such as `/lib/modules/<kernel_version>/` and any additional directories specified in the configuration files.
   - `insmod`: `insmod` requires you to provide the full path to the module file you want to insert into the kernel.

5. Error Handling:
   - `modprobe`: If a module fails to load or if there is an error, `modprobe` provides more informative error messages and can help in troubleshooting by showing the relevant error details.
   - `insmod`: `insmod` is a low-level command and provides minimal error handling. If an error occurs during module insertion, it usually results in a kernel panic or system crash.

In summary, `modprobe` is a higher-level command that automatically handles module dependencies, searches for modules, and provides better error handling. It is typically used for most module management tasks. On the other hand, `insmod` is a lower-level command that allows manual insertion of a single module into the kernel without any dependency resolution or configuration file processing. It is mainly used for specific scenarios where manual control is required, such as debugging or testing purposes.