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 makes use of the smb.conf parameter
52 <smbconfoption name="acl map full control">acl map full control</smbconfoption>
53 When set to yes (the default), this parameter will add in the FILE_DELETE_CHILD
54 bit on a returned ACE entry for a file (not a directory) that already
55 contains all file permissions except for FILE_DELETE and FILE_DELETE_CHILD.
56 This can prevent Windows applications that request GENERIC_ALL access
57 from getting ACCESS_DENIED errors when running against a filesystem
58 with NFSv4 compatible ACLs.
61 <para>This module is stackable.</para>
63 <para>Since Samba 4.0 all options are per share options.</para>
69 <title>OPTIONS</title>
75 <term>gpfs:sharemodes = [ yes | no ]</term>
78 Enable/Disable cross node sharemode handling for GPFS.
83 <command>yes(default)</command> - propagate sharemodes across all GPFS nodes.
86 <command>no</command> - do not propagate sharemodes across all GPFS nodes.
87 This should only be used if the GPFS file system is
88 exclusively exported by Samba. Access by local unix application or
89 NFS exports could lead to corrupted files.
97 <term>gpfs:leases = [ yes | no ]</term>
100 Enable/Disable cross node leases (oplocks) for GPFS.
101 You should also set the <command>oplocks</command> and <command>kernel oplocks</command>
102 options to the same value.
107 <command>yes(default)</command> - propagate leases across all GPFS nodes.
110 <command>no</command> - do not propagate leases across all GPFS nodes.
111 This should only be used if the GPFS file system is
112 exclusively exported by Samba. Access by local unix application or
113 NFS exports could lead to corrupted files.
122 <term>gpfs:hsm = [ yes | no ]</term>
125 Enable/Disable announcing if this FS has HSM enabled.
130 <command>no(default)</command> - Do not announce HSM.
133 <command>yes</command> - Announce HSM.
142 <term>gpfs:getrealfilename = [ yes | no ]</term>
145 Enable/Disable usage of the <command>gpfs_get_realfilename_path()</command> function.
146 This improves the casesensitive wildcard file name access.
151 <command>yes(default)</command> - use <command>gpfs_get_realfilename_path()</command>.
154 <command>no</command> - do not use <command>gpfs_get_realfilename_path()</command>.
155 It seems that <command>gpfs_get_realfilename_path()</command> doesn't work on AIX.
163 <term>gpfs:winattr = [ yes | no ]</term>
166 Enable/Disable usage of the windows attributes in GPFS.
167 GPFS is able to store windows file attributes e.g. HIDDEN,
168 READONLY, SYSTEM and others natively. That means Samba doesn't
169 need to map them to permission bits or extended attributes.
174 <command>no(default)</command> - do not use GPFS windows attributes.
177 <command>yes</command> - use GPFS windows attributes.
185 <term>gpfs:merge_writeappend = [ yes | no ]</term>
188 GPFS ACLs doesn't know about the 'APPEND' right.
189 This option lets Samba map the 'APPEND' right to 'WRITE'.
194 <command>yes(default)</command> - map 'APPEND' to 'WRITE'.
197 <command>no</command> - do not map 'APPEND' to 'WRITE'.
205 <term>gpfs:acl = [ yes | no ]</term>
208 This option lets Samba use or ignore GPFS ACLs.
213 <command>yes(default)</command> - use GPFS ACLs.
216 <command>no</command> - do not use GPFS ACLs and pass everything
217 to the next SMB_VFS module.
225 <term>gpfs:refuse_dacl_protected = [ yes | no ]</term>
228 As GPFS does not support the ACE4_FLAG_NO_PROPAGATE NFSv4 flag (which would be
229 the mapping for the DESC_DACL_PROTECTED flag), the status of this flag is
230 currently silently ignored by Samba. That means that if you deselect the "Allow
231 inheritable permissions..." checkbox in Windows' ACL dialog and then apply the
232 ACL, the flag will be back immediately.
235 To make sure that automatic migration with e.g. robocopy does not lead to
236 ACLs silently (and unintentionally) changed, you can set
237 <command>gpfs:refuse_dacl_protected = yes</command> to enable an explicit
238 check for this flag and if set, it will return NT_STATUS_NOT_SUPPORTED so
239 errors are shown up on the Windows side and the Administrator is aware of
240 the ACLs not being settable like intended
245 <command>no(default)</command> - ignore the DESC_DACL_PROTECTED flags.
248 <command>yes</command> - reject ACLs with DESC_DACL_PROTECTED.
256 <term>gpfs:dfreequota = [ yes | no ]</term>
259 Adjust reporting of the size and free space of a share
260 according to quotas. If this setting is "yes", a
261 request for size and free space will also evaluate the
262 user quota of the user requesting the data, the group
263 quota of the primary group of the user and the fileset
264 quota for the fileset containing the top level
265 directory of the share.
269 If any of the soft or hard quota limits has been
270 reached, the free space will be reported as 0. If a
271 quota is in place, but the limits have not been
272 reached, the free space will be reported according to
273 the space left in the quota. If more than one quota
274 applies the free space will be reported as the smallest
275 space left in those quotas. The size of the share
276 will be reported according to the quota usage. If more
277 than one quota applies, the smallest size will be
278 reported for the share size according to these quotas.
283 <command>yes</command> - include the quotas
284 when reporting the share size and free space
287 <command>no(default)</command> - do not include quotas,
288 simply report the size and free space of the file system
296 <term>gpfs:prealloc = [ yes | no ]</term>
299 If set to yes the gpfs_prealloc function will be used in the
300 fallocate callback when appropriate. If set to no gpfs_prealloc
301 will not be used. In both cases the system and libc calls are
307 <command>yes (default)</command> - Use gpfs_prealloc for the
311 <command>no</command> - Do not use gpfs_prealloc for the
321 <term>nfs4:mode = [ simple | special ]</term>
324 Controls substitution of special IDs (OWNER@ and GROUP@) on GPFS.
325 The use of mode simple is recommended.
326 In this mode only non inheriting ACL entries for the file owner
327 and group are mapped to special IDs.
330 <para>The following MODEs are understood by the module:</para>
332 <listitem><para><command>simple(default)</command> - use OWNER@ and GROUP@ special IDs for non inheriting ACEs only.</para></listitem>
333 <listitem><para><command>special(deprecated)</command> - use OWNER@ and GROUP@ special IDs in ACEs for all file owner and group ACEs.</para></listitem>
341 <term>nfs4:acedup = [dontcare|reject|ignore|merge]</term>
344 This parameter configures how Samba handles duplicate ACEs encountered in GPFS ACLs.
345 GPFS allows/creates duplicate ACE for different bits for same ID.
348 <para>Following is the behaviour of Samba for different values :</para>
350 <listitem><para><command>dontcare (default)</command> - copy the ACEs as they come</para></listitem>
351 <listitem><para><command>reject</command> - stop operation and exit with error on ACL set op</para></listitem>
352 <listitem><para><command>ignore</command> - don't include the second matching ACE</para></listitem>
353 <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>
360 <term>nfs4:chown = [yes|no]</term>
362 <para>This parameter allows enabling or disabling the chown supported
363 by the underlying filesystem. This parameter should be enabled with
364 care as it might leave your system insecure.</para>
365 <para>Some filesystems allow chown as a) giving b) stealing. It is the latter
366 that is considered a risk.</para>
368 <para>Following is the behaviour of Samba for different values : </para>
370 <listitem><para><command>yes</command> - Enable chown if as supported by the under filesystem</para></listitem>
371 <listitem><para><command>no (default)</command> - Disable chown</para></listitem>
377 <term>gpfs:syncio = [yes|no]</term>
379 <para>This parameter makes Samba open all files with O_SYNC.
380 This triggers optimizations in GPFS for workloads that
381 heavily share files.</para>
383 <para>Following is the behaviour of Samba for different
387 <listitem><para><command>yes</command> - Open files with O_SYNC
389 <listitem><para><command>no (default)</command> - Open files as
390 normal Samba would do
400 <title>EXAMPLES</title>
402 <para>A GPFS mount can be exported via Samba as follows :</para>
405 <smbconfsection name="[samba_gpfs_share]"/>
406 <smbconfoption name="vfs objects">gpfs</smbconfoption>
407 <smbconfoption name="path">/test/gpfs_mount</smbconfoption>
408 <smbconfoption name="nfs4: mode">special</smbconfoption>
409 <smbconfoption name="nfs4: acedup">merge</smbconfoption>
414 <title>CAVEATS</title>
416 Depending on the version of gpfs, the <command>libgpfs_gpl</command>
417 library or the <command>libgpfs</command> library is needed at
418 runtime by the <command>gpfs</command> VFS module:
419 Starting with gpfs 3.2.1 PTF8, the complete <command>libgpfs</command>
420 is available as open source and <command>libgpfs_gpl</command> does no
421 longer exist. With earlier versions of gpfs, only the
422 <command>libgpfs_gpl</command> library was open source and could be
426 At build time, only the header file <command>gpfs_gpl.h</command>
427 is required , which is a symlink to <command>gpfs.h</command> in
428 gpfs versions newer than 3.2.1 PTF8.
433 <title>VERSION</title>
434 <para>This man page is correct for version 3.0.25 of the Samba suite.
439 <title>AUTHOR</title>
441 <para>The original Samba software and related utilities
442 were created by Andrew Tridgell. Samba is now developed
443 by the Samba Team as an Open Source project similar
444 to the way the Linux kernel is developed.</para>
446 <para>The GPFS VFS module was created with contributions from
447 Volker Lendecke and the developers at IBM.
450 <para> This manpage was created by the IBM FSCC team </para>