1 .TH LFS-SETDIRSTRIPE 1 2017-11-07 "Lustre" "Lustre Utilities"
3 lfs setdirstripe, mkdir \- set striping pattern of a directory.
5 .B lfs setdirstripe [\fR-cdDHioTxX\fR] \fIDIR\fR...
8 Create a striped directory with specified striping pattern. This
10 sub-command is similar to
12 but is used to create a striped directory or set the default layout for
14 Can also be used to create directory with a foreign (free format) striping pattern (see
20 is an alias for this command.
23 .BR \-c ", " \-T ", " \-\-mdt\-count =\fICOUNT\fR
24 Stripe the new directory over
28 .BR \-i ", " \-\-mdt\-index =\fISTART_MDT_INDEX\fR[,\fIMDT_INDEX ...]
29 Use the MDT whose index is
31 as the master/starting MDT for the directory. If multiple
33 values are given, then the stripes will be allocated on the specified
34 MDT indices. If index -1 (default) is used, it will prefer to select
36 MDTs proportional to the free space and inodes on each.
38 .BR \-H ", " \-\-mdt-hash =\fIHASH_TYPE\fR
41 for the striped directory.
45 CRUSH hash algorithm. This is a consistent hash
46 algorithm, so minimum sub files need to relocate
47 during directory restripe.
50 Fowler-Noll-Vo (FNV-1a) hash algorithm. This provides
51 reasonably uniform, but not cryptographically strong,
52 hashing of the filename. (default)
55 Sum of ASCII characters modulo number of MDTs. This
56 provides weak hashing of the filename, and is suitable
57 for only testing or when the input is known to have
58 perfectly uniform distribution (e.g. sequential numbers).
61 .BR \-d ", " \-\-delete
62 Delete the default striping layout from the directory. New subdirectories
63 created in this directory will inherit the global default directory layout
64 (by default they will not be striped).
66 .BR \-D ", " \-\-default
67 Set the default striping pattern of subdirectories. Newly created
68 sub-directories will use the new default striping pattern,
69 but existing sub-directories will not be affected. The newly
70 created sub-directories will also inherit the specified default
71 striping pattern. Only default stripe count is supported for now.
73 Note that striping all directories across all MDTs by default is
75 recommended at this time, as the clients will have to do more RPCs to
76 create and access each directory, hurting performance rather than
77 improving it. Default striped directories are preferred for parent
79 where large subdirectories will be created (e.g. file-per-process
80 job output directories).
82 .BR \-o ", " \-\-mode =\fIMODE\fR
83 Set the file access permissions of the new directory to the specified
86 (typically octal), as with
88 It is not affected by the current
91 .BR \-\-foreign[=type]
92 Create a directory with a foreign (non-Lustre/free format, see
94 option) striping. Where
96 specifies a known foreign type (like
100 , ...) or a 32-bit numeric type.
102 .BR \-\-flags =\fI<hex>\fR
103 Specify a numeric bitmask of type-specific layout flags for the foreign layout.
105 .BR \-x ", " \-\-xattr =\fISTRING\fR
106 Specify a string to be used as a foreign (free format) striping.
108 .BR \-X ", " \-\-max-inherit = \fIMAX_INHERIT
109 Set the inherit depth of default directory layout. If non-zero, then
111 is the number of subdirectory levels for which this default layout is inherited,
112 up to a maximum of 250 levels, and is decremented by one when copying the
113 default layout to each new subdirectory, until zero and the default layout is
116 of -1 means the default layout is inherited for all subdirectories.
118 .BR \-\-max-inherit-rr = \fIMAX_INHERIT_RR
119 Set the round-robin inherit depth of the default directory layout, only when
123 is zero (unset), then new subdirectories are preferentially created on MDTs
124 with more free space and inodes if the MDTs are imbalanced. If non-zero, then
126 is the number of subdirectory levels, up to a maximum of 250 levels, for which
127 new subdirectories will be created in a round-robin manner across all available
128 MDTs, rather than using MDT space balancing for new subdirectories. Otherwise,
130 is decremented by one when copying the default layout to each new subdirectory,
131 until zero and round-robin is no longer used. It may be useful to set
133 to 2 or 3 when setting the default directory layout on the root of a
135 filesystem, so that top-level subdirectories are immediately spread
136 across MDTs, rather than waiting for the MDTs to become imbalanced.
137 Round-robin subdirectory creation is unlikely to be useful for existing
138 filesystems that already have many files and imbalanced MDTs, since space
139 balancing will already happen, and this will unnecessarily increase the number
140 of remote subdirectories (increasing overhead) without any benefit.
151 and create the directory on an MDT that is less full than the others.
155 command is only usable by root unless the
156 .B "mdt.*.enable_remote_dir_gid"
157 is set on the MDS via
159 to be either a non-zero numeric GID to limit it to a single group (e.g. the
160 .BR "operator " or " admin"
163 to allow any user/group to create remote directories. By default, it is
165 to limit remote/striped directories to only the root user.
167 The root directory of the file system is on MDT0000, and directories and
168 files inherit the MDT of their parent directory unless a different MDT is
169 specified with this command.
171 By default, only directories on MDT0000 can contain directories that are not on
172 the same MDT. However, if
173 .B "mdt.*.enable_remote_dir"
174 is set non-zero on an MDT (the default)
175 then it will allow creating remote directories that have parents other than
176 MDT0000. This is restricted to avoid creating directory trees that have
177 intermediate path components on a series different MDTs and become unavailable
178 if any of the intermediate MDTs are offline.
181 .B $ lfs setdirstripe -c 2 -i 1 -H all_char /mnt/lustre/dir1
182 This creates a directory striped on two MDTs, whose first stripe is on
184 (MDT index 1), and whose hash type is
187 .B $ lfs mkdir --foreign=symlink --xattr PUUID/CUUID /mnt/lustre/dir1
190 with foreign (non-lustre/free format)
192 striping/LMV EA value (symlink type).
196 command is part of the Lustre filesystem.
200 .BR lfs-getdirstripe (1),
201 .BR lfs-setstripe (1),