1VFS_GPFS(8)               System Administration tools              VFS_GPFS(8)
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NAME

6       vfs_gpfs - gpfs specific samba extensions like acls
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SYNOPSIS

9       vfs objects = gpfs
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DESCRIPTION

12       This VFS module is part of the samba(7) suite.
13
14       The gpfs VFS module is the home for all gpfs extensions that Samba
15       requires for proper integration with GPFS. It uses the GPL library
16       interfaces provided by GPFS.
17
18       Currently the gpfs vfs module provides extensions in following areas :
19
20              •   NFSv4 ACL Interfaces with configurable options for GPFS
21
22              •   Kernel oplock support on GPFS
23
24              •   Lease support on GPFS
25
26
27       NOTE: This module follows the posix-acl behaviour and hence allows
28       permission stealing via chown. Samba might allow at a later point in
29       time, to restrict the chown via this module as such restrictions are
30       the responsibility of the underlying filesystem than of Samba.
31
32       This module makes use of the smb.conf parameter acl map full control.
33       When set to yes (the default), this parameter will add in the
34       FILE_DELETE_CHILD bit on a returned ACE entry for a file (not a
35       directory) that already contains all file permissions except for
36       FILE_DELETE and FILE_DELETE_CHILD. This can prevent Windows
37       applications that request GENERIC_ALL access from getting ACCESS_DENIED
38       errors when running against a filesystem with NFSv4 compatible ACLs.
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40       This module is stackable.
41
42       Since Samba 4.0 all options are per share options.
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OPTIONS

45       gpfs:sharemodes = [ yes | no ]
46           Enable/Disable cross node sharemode handling for GPFS.
47
48                  •   yes(default) - propagate sharemodes across all GPFS
49                      nodes.
50
51                  •   no - do not propagate sharemodes across all GPFS nodes.
52                      This should only be used if the GPFS file system is
53                      exclusively exported by Samba. Access by local unix
54                      application or NFS exports could lead to corrupted
55                      files.
56
57
58       gpfs:leases = [ yes | no ]
59           Enable/Disable cross node leases (oplocks) for GPFS. You should
60           also set the oplocks and kernel oplocks options to the same value.
61
62                  •   yes(default) - propagate leases across all GPFS nodes.
63
64                  •   no - do not propagate leases across all GPFS nodes. This
65                      should only be used if the GPFS file system is
66                      exclusively exported by Samba. Access by local unix
67                      application or NFS exports could lead to corrupted
68                      files.
69
70
71       gpfs:hsm = [ yes | no ]
72           Enable/Disable announcing if this FS has HSM enabled.
73
74                  •   no(default) - Do not announce HSM.
75
76                  •   yes - Announce HSM.
77
78
79       gpfs:recalls = [ yes | no ]
80           When this option is set to no, an attempt to open an offline file
81           will be rejected with access denied. This helps preventing recall
82           storms triggered by careless applications like Finder and Explorer.
83
84                  •   yes(default) - Open files that are offline. This will
85                      recall the files from HSM.
86
87                  •   no - Reject access to offline files with access denied.
88                      This will prevent recalls of files from HSM. Using this
89                      setting also requires gpfs:hsm to be set to yes.
90
91
92       gpfs:getrealfilename = [ yes | no ]
93           Enable/Disable usage of the gpfs_get_realfilename_path() function.
94           This improves the casesensitive wildcard file name access.
95
96                  •   yes(default) - use gpfs_get_realfilename_path().
97
98                  •   no - do not use gpfs_get_realfilename_path(). It seems
99                      that gpfs_get_realfilename_path() doesn't work on AIX.
100
101
102       gpfs:winattr = [ yes | no ]
103           Enable/Disable usage of the windows attributes in GPFS. GPFS is
104           able to store windows file attributes e.g. HIDDEN, READONLY, SYSTEM
105           and others natively. That means Samba doesn't need to map them to
106           permission bits or extended attributes.
107
108                  •   no(default) - do not use GPFS windows attributes.
109
110                  •   yes - use GPFS windows attributes.
111
112
113       gpfs:acl = [ yes | no ]
114           This option lets Samba use or ignore GPFS ACLs.
115
116                  •   yes(default) - use GPFS ACLs.
117
118                  •   no - do not use GPFS ACLs and pass everything to the
119                      next SMB_VFS module.
120
121
122       gpfs:check_fstype = [ yes | no ]
123           Check for a mounted GPFS file system on access to a SMB share.
124
125                  •   yes(default) - Check that the SMB share path is on a
126                      GPFS file system. Share access will be denied when a
127                      different file system is found.
128
129                  •   no - skip check for GPFS file system on SMB share path.
130
131
132       gpfs:refuse_dacl_protected = [ yes | no ]
133           As GPFS does not support the ACE4_FLAG_NO_PROPAGATE NFSv4 flag
134           (which would be the mapping for the DESC_DACL_PROTECTED flag), the
135           status of this flag is currently silently ignored by Samba. That
136           means that if you deselect the "Allow inheritable permissions..."
137           checkbox in Windows' ACL dialog and then apply the ACL, the flag
138           will be back immediately.
139
140           To make sure that automatic migration with e.g. robocopy does not
141           lead to ACLs silently (and unintentionally) changed, you can set
142           gpfs:refuse_dacl_protected = yes to enable an explicit check for
143           this flag and if set, it will return NT_STATUS_NOT_SUPPORTED so
144           errors are shown up on the Windows side and the Administrator is
145           aware of the ACLs not being settable like intended
146
147                  •   no(default) - ignore the DESC_DACL_PROTECTED flags.
148
149                  •   yes - reject ACLs with DESC_DACL_PROTECTED.
150
151
152       gpfs:dfreequota = [ yes | no ]
153           Adjust reporting of the size and free space of a share according to
154           quotas. If this setting is "yes", a request for size and free space
155           will also evaluate the user quota of the user requesting the data
156           and the group quota of the primary group of the user. Fileset
157           quotas are not queried, since GPFS already provides the option
158           --dfreequota to reflect the fileset quota in the free space query.
159           Please use that option to include fileset quotas in the reported
160           disk space.
161
162           If any of the soft or hard quota limits has been reached, the free
163           space will be reported as 0. If a quota is in place, but the limits
164           have not been reached, the free space will be reported according to
165           the space left in the quota. If more than one quota applies the
166           free space will be reported as the smallest space left in those
167           quotas. The size of the share will be reported according to the
168           quota usage. If more than one quota applies, the smallest size will
169           be reported for the share size according to these quotas.
170
171                  •   yes - include the quotas when reporting the share size
172                      and free space
173
174                  •   no(default) - do not include quotas, simply report the
175                      size and free space of the file system
176
177
178       gpfs:settimes = [ yes | no ]
179           Use the gpfs_set_times API when changing the timestamps of a file
180           or directory. If the GPFS API is not available the old method of
181           using utime and the GPFS winattr call will be used instead.
182
183                  •   yes(default) - Use gpfs_set_times. Fall back to utime
184                      and winattr when it is not available.
185
186                  •   no - Do not use gpfs_set_times.
187
188
189       nfs4:mode = [ simple | special ]
190           Controls substitution of special IDs (OWNER@ and GROUP@) on GPFS.
191           The use of mode simple is recommended. In this mode only non
192           inheriting ACL entries for the file owner and group are mapped to
193           special IDs.
194
195           The following MODEs are understood by the module:
196
197                  •   simple(default) - use OWNER@ and GROUP@ special IDs for
198                      non inheriting ACEs only.
199
200                  •   special(deprecated) - use OWNER@ and GROUP@ special IDs
201                      in ACEs for all file owner and group ACEs.
202
203
204       nfs4:acedup = [dontcare|reject|ignore|merge]
205           This parameter configures how Samba handles duplicate ACEs
206           encountered in GPFS ACLs. GPFS allows/creates duplicate ACE for
207           different bits for same ID.
208
209           Following is the behaviour of Samba for different values :
210
211                  •   dontcare - copy the ACEs as they come
212
213                  •   reject (deprecated) - stop operation and exit with error
214                      on ACL set op
215
216                  •   ignore (deprecated) - don't include the second matching
217                      ACE
218
219                  •   merge (default) - bitwise OR the 2 ace.flag fields and 2
220                      ace.mask fields of the 2 duplicate ACEs into 1 ACE
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222
223       nfs4:chown = [yes|no]
224           This parameter allows enabling or disabling the chown supported by
225           the underlying filesystem. This parameter should be enabled with
226           care as it might leave your system insecure.
227
228           Some filesystems allow chown as a) giving b) stealing. It is the
229           latter that is considered a risk.
230
231           Following is the behaviour of Samba for different values :
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233                  •   yes - Enable chown if as supported by the under
234                      filesystem
235
236                  •   no (default) - Disable chown
237
238
239       gpfs:syncio = [yes|no]
240           This parameter makes Samba open all files with O_SYNC. This
241           triggers optimizations in GPFS for workloads that heavily share
242           files.
243
244           Following is the behaviour of Samba for different values:
245
246                  •   yes - Open files with O_SYNC
247
248                  •   no (default) - Open files as normal Samba would do
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250

EXAMPLES

252       A GPFS mount can be exported via Samba as follows :
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254                   [samba_gpfs_share]
255                vfs objects = gpfs
256                path = /test/gpfs_mount
257                nfs4: mode = special
258                nfs4: acedup = merge
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CAVEATS

261       Depending on the version of gpfs, the libgpfs_gpl library or the
262       libgpfs library is needed at runtime by the gpfs VFS module: Starting
263       with gpfs 3.2.1 PTF8, the complete libgpfs is available as open source
264       and libgpfs_gpl does no longer exist. With earlier versions of gpfs,
265       only the libgpfs_gpl library was open source and could be used at run
266       time.
267
268       At build time, only the header file gpfs_gpl.h is required, which is a
269       symlink to gpfs.h in gpfs versions newer than 3.2.1 PTF8.
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VERSION

272       This man page is part of version 4.16.2 of the Samba suite.
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AUTHOR

275       The original Samba software and related utilities were created by
276       Andrew Tridgell. Samba is now developed by the Samba Team as an Open
277       Source project similar to the way the Linux kernel is developed.
278
279       The GPFS VFS module was created with contributions from Volker Lendecke
280       and the developers at IBM.
281
282       This manpage was created by the IBM FSCC team
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286Samba 4.16.2                      06/13/2022                       VFS_GPFS(8)
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