Viewing: lustre_rmmod.8
.TH LUSTRE_RMMOD 8 2026-07-07 Lustre "Lustre Configuration Utilities"
.SH NAME
lustre_rmmod \- remove Lustre modules from the kernel
.SH SYNOPSIS
.SY lustre_rmmod
.RB [ -d | --debug-kernel "] [" -h | --help "] [" -w | --wait
.IR SECONDS "] [" MODULE " ...]"
.YS
.SH DESCRIPTION
.B lustre_rmmod
calls the
.BR rmmod (8)
utility to unload all of the Lustre kernel modules in the correct order
to handle dependencies between them.
This is useful/necessary when upgrading the kernel modules to ensure
that the newly-installed modules are used for mounting the filesystem.
Otherwise, if the system was not rebooted or modules unloaded before
remounting, it is possible that old modules are used.
.PP
If one or more
.I MODULE
arguments is given on the command line, then all dependencies of the
specified module(s) as well as the module itself are unloaded.
If no module is specified, then all Lustre kernel modules are unloaded.
.SH OPTIONS
.TP
.BR -d ", " --debug-kernel
Dump the Lustre kernel debug log using
.BR lctl-debug_kernel (8)
before unloading the last module.
This allows capturing full debug traces in case of issues during cleanup,
or when tracing memory leaks.
.TP
.BR -h ", " --help
Print a usage message and exit.
.TP
.BR -w ", " --wait " \fISECONDS"
Wait up to
.I SECONDS
seconds, total, for OBD devices to be cleaned up (according to
.BR lctl-device_list (8))
before trying to unload the modules,
to allow asynchronous device cleanup actions to complete after
.BR umount (8)
returns.
If
.IB SECONDS
is
.BR 0 ,
no devices are configured, or
.B lctl
returns an error, then there is no further wait before module unload.
.RS
.PP
An empty device list does not itself guarantee that a module's
reference count has reached zero, since some modules may
briefly retain a reference after the last device disappears.
If unloading a module fails, the remainder of the
.I SECONDS
budget is used to poll the module's reference count and retry the
unload once it reaches zero, rather than failing immediately.
.RE
.SH AVAILABILITY
.B lustre_rmmod
is part of the
.BR lustre (7)
filesystem package since release 1.6.0
.\" Added in commit v1.5.0-134-g113303973e
.SH SEE ALSO
.BR lctl (8),
.BR lctl-debug_kernel (8),
.BR lctl-device_list (8),
.BR rmmod (8),
.BR umount (8)
