.TH LCTL-POOL_ADD 8 2025-05-01 Lustre "Lustre Configuration Utilities"
.SH NAME
lctl-pool_add \- add OSTs to a named pool
.SH SYNOPSIS
.SY "lctl pool_add"
.RB [ --nowait | -n ]
.IR FSNAME . POOLNAME
.IR OST_INDEX1 " [" OST_INDEX2 ...]
.SY "lctl pool_add"
.RB [ --nowait | -n ]
.IR FSNAME . POOLNAME
.IR OST_RANGE1 " [" OST_RANGE2 ...]
.YS
.SH DESCRIPTION
Add one or more OSTs to the pool named
.I POOLNAME
in the filesystem named
.IR FSNAME .
There are several formats that the OSTs can be specified. Simplest is
to just specify a list of
.I OST_INDEX
numbers or OST names. It is also possible to specify an
.I OST_RANGE
expression of the form
.BI [ START - END ]
or
.BI [ START - END / STEP ]
that adds multiple OSTs with index numbers in the range from
.I START
to
.I END
(inclusive), optionally skipping every
.I STEP
index values.
.P
.BR NOTE:
After updating the MGS configuration, this command will wait up to 12s and
check if pools are updated on a client, unless the
.B --nowait
option is used.
If the MGS is on a separate node from the MDS, a Lustre client must
be mounted on the MGS node while the
.B lctl
commands are being run for this. Otherwise, the client check is skipped.
.P
This named list of OSTs can be used by
.BR lfs-setstripe (1)
to specify the OSTs on which new files can be created, though it is
important to note that the OSTs that make up a specific pool may change
over time, and it is the
.I poolname
used at creation time that is stored on each file, not necessarily
OSTs that are in the current pool.  The
.BR lfs-find (1)
command can locate files that were initially created on the specified
.IR poolname .
As well,
.BR lfs-df (1)
can show only the free space or inodes in a named pool.  The
.BR lfs-quota (1)
and
.BR lfs-setquota (1)
commands can use a pool name to get/set a quota limit for OSTs in the pool.
.SH OPTIONS
.TP
.BR -n ", " --nowait
Do not wait and check if pool is updated on a client.
This is useful when calling a lot of
.RB ' "lctl pool_*" '
commands in a row, to avoid waiting for each command to complete.
.SH EXAMPLES
Create a pool named
.B flash
in the
.B testfs
filesystem:
.RS
.EX
.B # lfs pool_new testfs.flash
.EE
.RE
.PP
Add OSTs numbered 8, 10, and 12 through 14 to the
.B testfs.flash
pool:
.RS
.EX
.B # lfs pool_add testfs.flash 8 10 12-14
.EE
.RE
.SH AVAILABILITY
.B lctl pool_add
is part of the
.BR lustre (7)
filesystem package since release 1.7.0
.\" Added in commit 1.6.0-1808-g665e36b780
.SH SEE ALSO
.BR lfs-df (1),
.BR lfs-find (1),
.BR lfs-setstripe (1),
.BR lustre (7),
.BR lctl (8),
.BR lctl-pool_new (8)