+.SS Changelogs
+.TP
+.BI changelog_register " [-n]"
+Register a new changelog user for a particular device. Changelog entries
+will not be purged beyond any registered users' set point. (See lfs changelog_clear.)
+.br
+.B -n
+Print only the ID of the newly registered user.
+.TP
+.BI changelog_deregister " <id>"
+Unregister an existing changelog user. If the user's "clear" record number
+is the minimum for the device, changelog records will be purged until the
+next minimum.
+.PP
+.SS Nodemap
+An identity mapping feature that facilitates mapping of client UIDs and GIDs to
+local file system UIDs and GIDs, while maintaining POSIX ownership, permissions,
+and quota.
+
+While the nodemap feature is enabled, all client file system access is subject
+to the nodemap identity mapping policy, which consists of the 'default' catchall
+nodemap, and any user-defined nodemaps. The 'default' nodemap maps all client
+identities to 99:99 (nobody:nobody). Administrators can define nodemaps for a
+range of client NIDs which map identities, and these nodemaps can be flagged as
+ 'trusted' so identities are accepted without translation, as well as flagged
+as 'admin' meaning that root is not squashed for these nodes.
+
+Note: In the current phase of implementation, to use the nodemap functionality
+you only need to enable and define nodemaps on the MDS. The MDSes must also be
+in a nodemap with the admin and trusted flags set. To use quotas with nodemaps,
+you must also use set_param to enable and define nodemaps on the OSS (matching
+what is defined on the MDS). Nodemaps do not currently persist, unless you
+define them with set_param and use the -P flag. Note that there is a hard limit
+to the number of changes you can persist over the lifetime of the file system.
+
+See also:
+
+.PP
+\fBlctl-nodemap-activate\fR(8)
+.RS 4
+Activate/deactivate the nodemap feature.
+.RE
+.PP
+\fBlctl-nodemap-add\fR(8)
+.RS 4
+Add a new nodemap, to which NID ranges, identities, and properties can be added.
+.RE
+.PP
+\fBlctl-nodemap-del\fR(8)
+.RS 4
+Delete an existing nodemap.
+.RE
+.PP
+\fBlctl-nodemap-add-range\fR(8)
+.RS 4
+Define a range of NIDs for a nodemap.
+.RE
+.PP
+\fBlctl-nodemap-del-range\fR(8)
+.RS 4
+Delete an existing NID range from a nodemap.
+.RE
+.PP
+\fBlctl-nodemap-add-idmap\fR(8)
+.RS 4
+Add a UID or GID mapping to a nodemap.
+.RE
+.PP
+\fBlctl-nodemap-del-idmap\fR(8)
+.RS 4
+Delete an existing UID or GID mapping from a nodemap.
+.RE
+.PP
+\fBlctl-nodemap-modify\fR(8)
+.RS 4
+Modify a nodemap property.
+.RE
+.PP
+\fBlctl-nodemap-set-fileset\fR(8)
+.RS 4
+Add a fileset to a nodemap.
+.RE
+.PP
+\fBlctl-nodemap-set-sepol\fR(8)
+.RS 4
+Set SELinux policy info on a nodemap.
+.RE
+.SS Configuration logs
+.TP
+.BI clear_conf " <device|fsname>"
+This command runs on MGS node having MGS device mounted with -o
+nosvc. It cleans up configuration files stored in the CONFIGS/ directory
+of any records marked SKIP. If the device name is given, then the
+specific logs for that filesystem (e.g. testfs-MDT0000) is processed.
+Otherwise, if a filesystem name is given then all configuration files for the
+specified filesystem are cleared.
+.PP
+.SS LFSCK
+An on-line Lustre consistency check and repair tool. It is used for totally
+replacing the old lfsck tool for kinds of Lustre inconsistency verification,
+including: corrupted or lost OI mapping, corrupted or lost link EA, corrupted
+or lost FID in name entry, dangling name entry, multiple referenced name entry,
+unmatched MDT-object and name entry pairs, orphan MDT-object, incorrect
+MDT-object links count, corrupted namespace, corrupted or lost lov EA, lost
+OST-object, multiple referenced OST-object, unmatched MDT-object and OST-object
+pairs, orphan OST-object, and so on.
+
+See also:
+
+.PP
+\fBlctl-lfsck-start\fR(8)
+.RS 4
+Start LFSCK on the specified MDT or OST device with specified parameters.
+.RE
+.PP
+\fBlctl-lfsck-stop\fR(8)
+.RS 4
+Stop LFSCK on the specified MDT or OST device.
+.RE
+.PP
+\fBlctl-lfsck-query\fR(8)
+.RS 4
+Get the LFSCK global status via the specified MDT device.
+.RE
+
+.SS BARRIER
+The tools set for write (modify) barrier on all MDTs. For detail, please see:
+.PP
+\fBlctl-barrier\fR(8)
+.RS 4
+
+.SS SNAPSHOT
+ZFS backend based snapshot tools set. The tool loads system configuration
+from the file
+.B /etc/ldev.conf
+on the MGS, and call related ZFS commands to
+maintain Lustre snapshot pieces on all targets (MGS/MDT/OST).
+The configuration file
+.B /etc/ldev.conf
+is not only for snapshot, but also
+for other purpose. The format is:
+ <host> foreign/- <label> <device> [journal-path]/- [raidtab]
+
+The format of
+.I <label>
+is:
+ fsname-<role><index> or <role><index>
+
+The format of
+.I <device>
+is:
+ [md|zfs:][pool_dir/]<pool>/<filesystem>
+
+Snapshot only uses the fields <host>, <label> and <device>.
+
+.br
+.B Example:
+.br
+.B
+# cat /etc/ldev.conf
+.br
+ host-mdt1 - myfs-MDT0000 zfs:/tmp/myfs-mdt1/mdt1
+ host-mdt2 - myfs-MDT0001 zfs:myfs-mdt2/mdt2
+ host-ost1 - OST0000 zfs:/tmp/myfs-ost1/ost1
+ host-ost2 - OST0001 zfs:myfs-ost2/ost2
+
+See also:
+
+.PP
+\fBlctl-snapshot-create\fR(8)
+.RS 4
+Create snapshot with the given name.
+.RE
+.PP
+\fBlctl-snapshot-destroy\fR(8)
+.RS 4
+Destroy the specified snapshot.
+.RE
+.PP
+\fBlctl-snapshot-modify\fR(8)
+.RS 4
+Modify the specified snapshot.
+.RE
+.PP
+\fBlctl-snapshot-list\fR(8)
+.RS 4
+Query the snapshot information.
+.RE
+.PP
+\fBlctl-snapshot-mount\fR(8)
+.RS 4
+Mount the specified snapshot.
+.RE
+.PP
+\fBlctl-snapshot-umount\fR(8)
+.RS 4
+Umount the specified snapshot.
+.RE
+