1 <?xml version="1.0" encoding="iso-8859-1"?>
2 <!DOCTYPE refentry PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">
3 <refentry id="vfs_gpfs.8">
6 <refentrytitle>vfs_gpfs</refentrytitle>
7 <manvolnum>8</manvolnum>
8 <refmiscinfo class="source">Samba</refmiscinfo>
9 <refmiscinfo class="manual">System Administration tools</refmiscinfo>
10 <refmiscinfo class="version">4.0</refmiscinfo>
15 <refname>vfs_gpfs</refname>
16 <refpurpose>gpfs specific samba extensions like acls and prealloc</refpurpose>
21 <command>vfs objects = gpfs</command>
26 <title>DESCRIPTION</title>
28 <para>This VFS module is part of the
29 <citerefentry><refentrytitle>samba</refentrytitle>
30 <manvolnum>7</manvolnum></citerefentry> suite.</para>
32 <para>The <command>gpfs</command> VFS module is the home
33 for all gpfs extensions that Samba requires for proper integration
34 with GPFS. It uses the GPL library interfaces provided by GPFS.
37 <para>Currently the gpfs vfs module provides extensions in following areas :
39 <listitem><para>NFSv4 ACL Interfaces with configurable options for GPFS</para></listitem>
40 <listitem><para>Kernel oplock support on GPFS</para></listitem>
41 <listitem><para>Lease support on GPFS</para></listitem>
45 <para><command>NOTE:</command>This module follows the posix-acl behaviour
46 and hence allows permission stealing via chown. Samba might allow at a later
47 point in time, to restrict the chown via this module as such restrictions
48 are the responsibility of the underlying filesystem than of Samba.
51 <para>This module is stackable.</para>
53 <para>Since Samba 4.0 all options are per share options.</para>
59 <title>OPTIONS</title>
65 <term>gpfs:sharemodes = [ yes | no ]</term>
68 Enable/Disable cross node sharemode handling for GPFS.
73 <command>yes(default)</command> - propagate sharemodes across all GPFS nodes.
76 <command>no</command> - do not propagate sharemodes across all GPFS nodes.
77 This should only be used if the GPFS file system is
78 exclusively exported by Samba. Access by local unix application or
79 NFS exports could lead to corrupted files.
87 <term>gpfs:leases = [ yes | no ]</term>
90 Enable/Disable cross node leases (oplocks) for GPFS.
91 You should also set the <command>oplocks</command> and <command>kernel oplocks</command>
92 options to the same value.
97 <command>yes(default)</command> - propagate leases across all GPFS nodes.
100 <command>no</command> - do not propagate leases across all GPFS nodes.
101 This should only be used if the GPFS file system is
102 exclusively exported by Samba. Access by local unix application or
103 NFS exports could lead to corrupted files.
112 <term>gpfs:hsm = [ yes | no ]</term>
115 Enable/Disable announcing if this FS has HSM enabled.
120 <command>no(default)</command> - Do not announce HSM.
123 <command>yes</command> - Announce HSM.
132 <term>gpfs:getrealfilename = [ yes | no ]</term>
135 Enable/Disable usage of the <command>gpfs_get_realfilename_path()</command> function.
136 This improves the casesensitive wildcard file name access.
141 <command>yes(default)</command> - use <command>gpfs_get_realfilename_path()</command>.
144 <command>no</command> - do not use <command>gpfs_get_realfilename_path()</command>.
145 It seems that <command>gpfs_get_realfilename_path()</command> doesn't work on AIX.
153 <term>gpfs:winattr = [ yes | no ]</term>
156 Enable/Disable usage of the windows attributes in GPFS.
157 GPFS is able to store windows file attributes e.g. HIDDEN,
158 READONLY, SYSTEM and others natively. That means Samba doesn't
159 need to map them to permission bits or extended attributes.
164 <command>no(default)</command> - do not use GPFS windows attributes.
167 <command>yes</command> - use GPFS windows attributes.
175 <term>gpfs:merge_writeappend = [ yes | no ]</term>
178 GPFS ACLs doesn't know about the 'APPEND' right.
179 This option lets Samba map the 'APPEND' right to 'WRITE'.
184 <command>yes(default)</command> - map 'APPEND' to 'WRITE'.
187 <command>no</command> - do not map 'APPEND' to 'WRITE'.
195 <term>gpfs:acl = [ yes | no ]</term>
198 This option lets Samba use or ignore GPFS ACLs.
203 <command>yes(default)</command> - use GPFS ACLs.
206 <command>no</command> - do not use GPFS ACLs and pass everything
207 to the next SMB_VFS module.
215 <term>gpfs:refuse_dacl_protected = [ yes | no ]</term>
218 As GPFS does not support the ACE4_FLAG_NO_PROPAGATE NFSv4 flag (which would be
219 the mapping for the DESC_DACL_PROTECTED flag), the status of this flag is
220 currently silently ignored by Samba. That means that if you deselect the "Allow
221 inheritable permissions..." checkbox in Windows' ACL dialog and then apply the
222 ACL, the flag will be back immediately.
225 To make sure that automatic migration with e.g. robocopy does not lead to
226 ACLs silently (and unintentionally) changed, you can set
227 <command>gpfs:refuse_dacl_protected = yes</command> to enable an explicit
228 check for this flag and if set, it will return NT_STATUS_NOT_SUPPORTED so
229 errors are shown up on the Windows side and the Administrator is aware of
230 the ACLs not being settable like intended
235 <command>no(default)</command> - ignore the DESC_DACL_PROTECTED flags.
238 <command>yes</command> - reject ACLs with DESC_DACL_PROTECTED.
246 <term>gpfs:dfreequota = [ yes | no ]</term>
249 Adjust reporting of the size and free space of a share
250 according to quotas. If this setting is "yes", a
251 request for size and free space will also evaluate the
252 user quota of the user requesting the data, the group
253 quota of the primary group of the user and the fileset
254 quota for the fileset containing the top level
255 directory of the share.
259 If any of the soft or hard quota limits has been
260 reached, the free space will be reported as 0. If a
261 quota is in place, but the limits have not been
262 reached, the free space will be reported according to
263 the space left in the quota. If more than one quota
264 applies the free space will be reported as the smallest
265 space left in those quotas. The size of the share
266 will be reported according to the quota usage. If more
267 than one quota applies, the smallest size will be
268 reported for the share size according to these quotas.
273 <command>yes</command> - include the quotas
274 when reporting the share size and free space
277 <command>no(default)</command> - do not include quotas,
278 simply report the size and free space of the file system
286 <term>gpfs:prealloc = [ yes | no ]</term>
289 If set to yes the gpfs_prealloc function will be used in the
290 fallocate callback when appropriate. If set to no gpfs_prealloc
291 will not be used. In both cases the system and libc calls are
297 <command>yes (default)</command> - Use gpfs_prealloc for the
301 <command>no</command> - Do not use gpfs_prealloc for the
311 <term>nfs4:mode = [ simple | special ]</term>
314 Enable/Disable substitution of special IDs on GPFS. This parameter
315 should not affect the windows users in anyway. It only ensures that Samba
316 sets the special IDs - OWNER@ and GROUP@ ( mappings to simple uids )
317 that are relevant to GPFS.
320 <para>The following MODEs are understood by the module:</para>
322 <listitem><para><command>simple(default)</command> - do not use special IDs in GPFS ACEs</para></listitem>
323 <listitem><para><command>special</command> - use special IDs in GPFS ACEs. </para> </listitem>
331 <term>nfs4:acedup = [dontcare|reject|ignore|merge]</term>
334 This parameter configures how Samba handles duplicate ACEs encountered in GPFS ACLs.
335 GPFS allows/creates duplicate ACE for different bits for same ID.
338 <para>Following is the behaviour of Samba for different values :</para>
340 <listitem><para><command>dontcare (default)</command> - copy the ACEs as they come</para></listitem>
341 <listitem><para><command>reject</command> - stop operation and exit with error on ACL set op</para></listitem>
342 <listitem><para><command>ignore</command> - don't include the second matching ACE</para></listitem>
343 <listitem><para><command>merge</command> - bitwise OR the 2 ace.flag fields and 2 ace.mask fields of the 2 duplicate ACEs into 1 ACE</para></listitem>
350 <term>nfs4:chown = [yes|no]</term>
352 <para>This parameter allows enabling or disabling the chown supported
353 by the underlying filesystem. This parameter should be enabled with
354 care as it might leave your system insecure.</para>
355 <para>Some filesystems allow chown as a) giving b) stealing. It is the latter
356 that is considered a risk.</para>
358 <para>Following is the behaviour of Samba for different values : </para>
360 <listitem><para><command>yes</command> - Enable chown if as supported by the under filesystem</para></listitem>
361 <listitem><para><command>no (default)</command> - Disable chown</para></listitem>
367 <term>gpfs:syncio = [yes|no]</term>
369 <para>This parameter makes Samba open all files with O_SYNC.
370 This triggers optimizations in GPFS for workloads that
371 heavily share files.</para>
373 <para>Following is the behaviour of Samba for different
377 <listitem><para><command>yes</command> - Open files with O_SYNC
379 <listitem><para><command>no (default)</command> - Open files as
380 normal Samba would do
390 <title>EXAMPLES</title>
392 <para>A GPFS mount can be exported via Samba as follows :</para>
395 <smbconfsection name="[samba_gpfs_share]"/>
396 <smbconfoption name="vfs objects">gpfs</smbconfoption>
397 <smbconfoption name="path">/test/gpfs_mount</smbconfoption>
398 <smbconfoption name="nfs4: mode">special</smbconfoption>
399 <smbconfoption name="nfs4: acedup">merge</smbconfoption>
404 <title>CAVEATS</title>
406 Depending on the version of gpfs, the <command>libgpfs_gpl</command>
407 library or the <command>libgpfs</command> library is needed at
408 runtime by the <command>gpfs</command> VFS module:
409 Starting with gpfs 3.2.1 PTF8, the complete <command>libgpfs</command>
410 is available as open source and <command>libgpfs_gpl</command> does no
411 longer exist. With earlier versions of gpfs, only the
412 <command>libgpfs_gpl</command> library was open source and could be
416 At build time, only the header file <command>gpfs_gpl.h</command>
417 is required , which is a symlink to <command>gpfs.h</command> in
418 gpfs versions newer than 3.2.1 PTF8.
423 <title>VERSION</title>
424 <para>This man page is correct for version 3.0.25 of the Samba suite.
429 <title>AUTHOR</title>
431 <para>The original Samba software and related utilities
432 were created by Andrew Tridgell. Samba is now developed
433 by the Samba Team as an Open Source project similar
434 to the way the Linux kernel is developed.</para>
436 <para>The GPFS VFS module was created with contributions from
437 Volker Lendecke and the developers at IBM.
440 <para> This manpage was created by the IBM FSCC team </para>