.SH NAME
lfs df \- report Lustre filesystem disk usage
.SH SYNOPSIS
-.BR "lfs df" " [" -i "] [" -h "] [" --lazy "] [" --pool | -p
+.BR "lfs df" " [" -i "] [" -h | -H ]
+.RB [ --lazy | -l ]
+.RB [ --pool | -p
.IR <fsname> [. <pool> ]]
-.RB [ -v ]
+.RB [ --verbose | -v ]
.RI [ path ]
.SH DESCRIPTION
.B lfs df
filesystem currently mounted on that node, or for the filesystem
that contains
.I path
-if given. It displaying current usage and totals for each MDT and
+if given. It displays the current usage and totals for each MDT and
OST separately, as well as a per-filesystem summary that matches
.BR df (1)
output for each filesystem.
+.PP
+By default
+.B lfs df
+reports the
+.I space
+usage of the OSTs (the MDT space usage is shown only for reference). With
+.B -i
+it reports the
+.I inode
+(object) usage for each target and in the summary. For ZFS-backed
+targets, the
+.B IUsed
+count accurately reflects the number of in-use objects on each target,
+but the
+.B Inodes
+total and
+.B Free
+inode counts are
+.I estimated
+based on the current average (mean) space used per object on each target,
+and may fluctuate over time to reflect the current usage pattern of
+the target. The estimate becomes more accurate as the target becomes
+more full, assuming the usage pattern is consistent.
+.PP
+.B lfs df
+may also report additional target status as the last column in the
+display, if there are issues with that target. States include:
+.RS 0.3i
+.TP
+.B D: degraded
+The target has a failed drive in the RAID device, or is undergoing
+RAID reconstruction. This state is marked on the server automatically
+for ZFS targets via
+.BR zed (8),
+or a (user-supplied) script that monitors the target device and sets
+.B 'lctl set_param obdfilter.\fI<target>\fB.degraded=1'
+on the OST. This target will be avoided for new allocations, but
+will still be used for existing files located there or if there are
+not enough non-degraded OSTs to make up a widely-striped file.
+.TP
+.B N: no-precreate
+The target is configured to deny object precreation by the
+.B 'lctl set_param obdfilter.\fI<target>\fB.no_precreate=1'
+parameter or
+.B '-o no_precreate'
+mount option. This may be done to add an OST to the filesystem without
+allowing objects to be allocated on it yet, or for other reasons.
+.TP
+.B R: read-only
+The target filesystem is marked read-only due to filesystem
+corruption detected by ldiskfs or ZFS. No modifications are
+allowed on this OST, and it needs to have
+.BR e2fsck (8)
+or
+.BR zpool (8) " scrub"
+run to repair the underlying filesystem.
+.TP
+.B S: out-of-space
+The target filesystem has less than the minimum required free space and
+will not be used for new object allocations until it has more free space.
+.TP
+.B I: out-of-inodes
+The target filesystem has less than the minimum required free inodes and
+will not be used for new object allocations until it has more free inodes.
+.TP
+.B f: flash
+The target filesystem is using a flash (non-rotational) storage device.
+This lower-case status is only shown in conjunction with the
+.B -v
+option, since it is not an error condition.
+.RE
.SH OPTIONS
The various options supported by
.B lfs df
.TP
.BR -h ", " --human-readable
Print output in a human readable format (e.g. 16.3T, 4.25P).
-Suffixes are SI base-2 units (i.e. 1 GiB = 1024 MiB).
+Suffixes are base-2 units (i.e. 1 GiB = 1024 MiB).
+.TP
+.BR -H ", " --si
+Like
+.BR -h ,
+but suffixes are SI base-10 units (i.e. 1 GB = 1000 MB).
.TP
.BR -i ", " --inodes
Print information about the inode usage and totals for the MDTs and
-OSTs rather than space usage.
+OSTs rather than space usage. Note that the
+.B Inodes
+total,
+.BR IUsed ,
+and
+.B IFree
+counts typically reflect the
+.I sum
+of values from the MDTs. If the total number of objects available
+on the OSTs is smaller (factoring in the filesystem default
+.BR stripe_count ,
+as one OST object is used for each stripe in a file)
+then the reported
+.B Inodes
+and
+.B IFree
+values will be reduced to reflect the
+.I minimum
+number of files that could potentially be created with the default
+stripe count. The actual total number of files that can be created
+may be different.
.TP
.BR -l ", " --lazy
Do not attempt to contact any OST or MDT not currently connected to
the client. This avoids blocking the
.B lfs df
-output if an OST is down, and only returns the space on the OSTs that
-can currently be accessed.
+output if a target is offline or unreachable, and only returns the
+space on OSTs that can currently be accessed.
.TP
-.BR -p ", " --pool=\fR[\fIfsname\fR.]\fIpool
-Show only OSTs that are in the specified
+.BR -p ", " --pool= [ \fIfsname\fR .] \fIpool\fR
+Limit the usage to report only MDTs and OSTs that are in the specified
.IR pool .
If multiple filesystems are mounted, list OSTs in
.I pool
.BI "lfs df --pool=" "pool /mnt/fsname"
.TP
.BR -v ", " --verbose
-Show deactivated MDTs and OSTs in the listing. By default, any
+Show deactivated MDTs and OSTs in the listing, along with any
+additional status flags for each MDT and OST. By default, any
MDTs and OSTs that are deactivated by the administrator are not shown.
However, targets that are only temporarily inaccessible are still shown.
.SH EXAMPLES
.TP
-.B $ lfs df -h /mnt/testfs
+.B $ lfs df -hv /mnt/testfs
Lists space usage per OST and MDT for the
.B testfs
filesystem in human readable format.
+.PP
+.RS 0.75i
+UUID bytes Used Avail Use% Mounted on
+.br
+testfs-MDT0000_UUID 13.0G 1.2G 11.0G 10% /testfs[MDT:0]
+.br
+testfs-OST0000_UUID 3.6T 2.9T 585.7G 84% /testfs[OST:0]
+.br
+testfs-OST0001_UUID 3.6T 3.1T 472.5G 87% /testfs[OST:1] D
+.br
+testfs-OST0002_UUID 3.6T 3.0T 570.3G 84% /testfs[OST:2] DR
+.br
+OST0003 : inactive device
+.br
+testfs-OST0006_UUID 5.4T 4.9T 417.8G 92% /testfs[OST:3]
+.br
+
+filesystem_summary: 16.2T 13.8T 2.0T 88% /testfs
+.br
+.RE
+.PP
+The above example output shows that
+.B OST0003
+is currently temporarily inactive or offline, while
+.B OST0004
+and
+.B OST0005
+are not shown at all, either because they are marked permanently offline
+by the administrator (via
+.BR "lctl set_param -P osc.testfs-OST000[45].active=0" )
+or they were never added to the filesystem. The
+.B testfs-OST0001
+and
+.B testfs-OST0002
+targets are currently marked
+.BR D egraded
+(perhaps they both share the same underlying storage controller),
+while
+.B testfs-OST0002
+is also marked
+.BR R ead-only,
+after detecting non-recoverable corruption in the backing filesystem.
.TP
-.B $ lfs df -i
+.B $ lfs df -iH
List inode usage per OST and MDT for all mounted Lustre filesystems.
+.RS 0.75i
+UUID Inodes IUsed IFree IUse% Mounted on
+.br
+testfs-MDT0000_UUID 932.2k 884.6k 47.6k 95% /testfs[MDT:0]
+.br
+testfs-OST0000_UUID 267.5k 179.6k 87.8k 67% /testfs[OST:0]
+.br
+testfs-OST0001_UUID 268.9k 173.5k 95.4k 64% /testfs[OST:1] D
+.br
+testfs-OST0002_UUID 267.5k 169.6k 97.9k 63% /testfs[OST:2] DR
+.br
+OST0003 : inactive device
+.br
+testfs-OST0006_UUID 426.1k 377.4k 48.7k 88% /testfs[OST:3]
+.br
+
+filesystem_summary: 932.1k 884.6k 47.6k 95% /testfs
+.br
+.RE
.TP
.B $ lfs df --pool ssd /mnt/testfs
List space usage for only the
git://git.whamcloud.com / fs / lustre-release.git / blobdiff