NAME
modprobe.d, modprobe.confmodprobe.conf — Configuration directory/file
for modprobe
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. All files underneath the
/etc/modprobe.d directory which end with the .conf extension specify
those options as required. (the /etc/modprobe.conf file can also be
used if it exists, but that will be removed in a future version). They
can also be used 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 interchangable throughout all the module
commands as underscore conversion happens automatically.
The format of and files under modprobe.d and /etc/modprobe.conf is
simple: 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 file a bit
neater.
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.
COMPATIBILITY
A future version of module-init-tools 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.
COPYRIGHT
This manual page originally Copyright 2004, Rusty Russell, IBM
Corporation. Maintained by Jon Masters and others.
SEE ALSO
modprobe(8), modules.dep(5)
modprobe.conf(5)