# modprobe.d

## NAME



           modprobe.d - Configuration directory for modprobe
    


## SYNOPSIS



           /etc/modprobe.d/*.conf
    
           /run/modprobe.d/*.conf
    
           /usr/local/lib/modprobe.d/*.conf
    
           /usr/local/lib/modprobe.d/*.conf
    
           /lib/modprobe.d/*.conf
    


## DESCRIPTION



           Because the **modprobe** command can add or remove more than one
           module, due to modules having dependencies, we need a method of
           specifying what options are to be used with those modules. One can
           also use them to create convenient aliases: alternate names for a
           module, or they can override the normal **modprobe** behavior
           altogether for those with special requirements (such as inserting
           more than one module).
    
           Note that module and alias names (like other module names) can
           have - or _ in them: both are interchangeable throughout all the
           module commands as underscore conversion happens automatically.
    


## CONFIGURATION FORMAT



           The configuration files contain one command per line, with blank
           lines and lines starting with '#' ignored (useful for adding
           comments). A '\' at the end of a line causes it to continue on the
           next line, which makes the files a bit neater.
    
           See the COMMANDS section below for more.
    


## CONFIGURATION DIRECTORIES AND PRECEDENCE



           Configuration files are read from directories in listed in
           SYNOPSIS in that order of precedence. Once a file of a given
           filename is loaded, any file of the same name in subsequent
           directories is ignored.
    
           All configuration files are sorted in lexicographic order,
           regardless of the directory they reside in. Configuration files
           can either be completely replaced (by having a new configuration
           file with the same name in a directory of higher priority) or
           partially replaced (by having a configuration file that is ordered
           later).
    
           NOTE: The configuration directories may be altered via the
           MODPROBE_OPTIONS environment variable. See the ENVIRONMENT section
           in modprobe(8).
    


## COMMANDS



           alias _wildcard modulename_
               This allows you to give alternate names for a module. For
               example: "alias my-mod really_long_modulename" means you can
               use "modprobe my-mod" instead of "modprobe
               really_long_modulename". You can also use shell-style
               wildcards, so "alias my-mod* really_long_modulename" means
               that "modprobe my-mod-something" has the same effect. You
               can't have aliases to other aliases (that way lies madness),
               but aliases can have options, which will be added to any other
               options.
    
               Note that modules can also contain their own aliases, which
               you can see using **modinfo**. These aliases are used as a last
               resort (ie. if there is no real module, **install** , **remove** , or
               **alias** command in the configuration).
    
           blacklist _modulename_
               Modules can contain their own aliases: usually these are
               aliases describing the devices they support, such as
               "pci:123...". These "internal" aliases can be overridden by
               normal "alias" keywords, but there are cases where two or more
               modules both support the same devices, or a module invalidly
               claims to support a device that it does not: the **blacklist**
               keyword indicates that all of that particular module's
               internal aliases are to be ignored.
    
           install _modulename command..._
               This command instructs **modprobe** to run your command instead of
               inserting the module in the kernel as normal. The command can
               be any shell command: this allows you to do any kind of
               complex processing you might wish. For example, if the module
               "fred" works better with the module "barney" already installed
               (but it doesn't depend on it, so **modprobe** won't automatically
               load it), you could say "install fred /sbin/modprobe barney;
               /sbin/modprobe --ignore-install fred", which would do what you
               wanted. Note the **--ignore-install** , which stops the second
               **modprobe** from running the same **install** command again. See also
               **remove** below.
    
               The long term future of this command as a solution to the
               problem of providing additional module dependencies is not
               assured and it is intended to replace this command with a
               warning about its eventual removal or deprecation at some
               point in a future release. Its use complicates the automated
               determination of module dependencies by distribution
               utilities, such as mkinitrd (because these now need to somehow
               interpret what the **install** commands might be doing. In a
               perfect world, modules would provide all dependency
               information without the use of this command and work is
               underway to implement soft dependency support within the Linux
               kernel.
    
               If you use the string "$CMDLINE_OPTS" in the command, it will
               be replaced by any options specified on the modprobe command
               line. This can be useful because users expect "modprobe fred
               opt=1" to pass the "opt=1" arg to the module, even if there's
               an install command in the configuration file. So our above
               example becomes "install fred /sbin/modprobe barney;
               /sbin/modprobe --ignore-install fred $CMDLINE_OPTS"
    
           options _modulename option..._
               This command allows you to add options to the module
               _modulename_ (which might be an alias) every time it is inserted
               into the kernel: whether directly (using **modprobe** _modulename_)
               or because the module being inserted depends on this module.
    
               All options are added together: they can come from an **option**
               for the module itself, for an alias, and on the command line.
    
           remove _modulename command..._
               This is similar to the **install** command above, except it is
               invoked when "modprobe -r" is run.
    
           softdep _modulename_ pre: _modules..._ post: _modules..._
               The **softdep** command allows you to specify soft, or optional,
               module dependencies. _modulename_ can be used without these
               optional modules installed, but usually with some features
               missing. For example, a driver for a storage HBA might require
               another module be loaded in order to use management features.
    
               pre-deps and post-deps modules are lists of names and/or
               aliases of other modules that modprobe will attempt to install
               (or remove) in order before and after the main module given in
               the _modulename_ argument.
    
               Example: Assume "softdep c pre: a b post: d e" is provided in
               the configuration. Running "modprobe c" is now equivalent to
               "modprobe a b c d e" without the softdep. Flags such as --use-
               blacklist are applied to all the specified modules, while
               module parameters only apply to module c.
    
               Note: if there are **install** or **remove** commands with the same
               _modulename_ argument, **softdep** takes precedence.
    
           weakdep _modulename modules..._
               The **weakdep** command allows you to specify weak module
               dependencies. Those are similar to pre softdep, with the
               difference that userspace doesn't attempt to load that
               dependency before the specified module. Instead the kernel may
               request one or multiple of them during module probe, depending
               on the hardware it's binding to. The purpose of weak module is
               to allow a driver to specify that a certain dependency may be
               needed, so it should be present in the filesystem (e.g. in
               initramfs) when that module is probed.
    
               Example: Assume "weakdep c a b". A program creating an
               initramfs knows it should add a, b, and c to the filesystem
               since a and b may be required/desired at runtime. When c is
               loaded and is being probed, it may issue calls to
               request_module() causing a or b to also be loaded.
    


## COMPATIBILITY



           A future version of kmod will come with a strong warning to avoid
           use of the **install** as explained above. This will happen once
           support for soft dependencies in the kernel is complete. That
           support will complement the existing softdep support within this
           utility by providing such dependencies directly within the
           modules.
    


## BUGS



           Please direct any bug reports to kmod's issue tracker at
           https://github.com/kmod-project/kmod/issues/ alongside with
           version used, steps to reproduce the problem and the expected
           outcome.
    


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