1VFS_GPFS(8) System Administration tools VFS_GPFS(8)
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6 vfs_gpfs - gpfs specific samba extensions like acls and prealloc
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9 vfs objects = gpfs
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12 This VFS module is part of the samba(7) suite.
13 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 Currently the gpfs vfs module provides extensions in following areas :
19 · NFSv4 ACL Interfaces with configurable options for GPFS
21 · Kernel oplock support on GPFS
23 · Lease support on GPFS
25 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 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.
39 This module is stackable.
41 Since Samba 4.0 all options are per share options.
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45 gpfs:sharemodes = [ yes | no ]
46 Enable/Disable cross node sharemode handling for GPFS.
47 · yes(default) - propagate sharemodes across all GPFS nodes.
49 · no - do not propagate sharemodes across all GPFS nodes. This
51 should only be used if the GPFS file system is exclusively
52 exported by Samba. Access by local unix application or NFS
53 exports could lead to corrupted files.
54 gpfs:leases = [ yes | no ]
57 Enable/Disable cross node leases (oplocks) for GPFS. You should
58 also set the oplocks and kernel oplocks options to the same value.
59 · yes(default) - propagate leases across all GPFS nodes.
61 · no - do not propagate leases across all GPFS nodes. This
63 should only be used if the GPFS file system is exclusively
64 exported by Samba. Access by local unix application or NFS
65 exports could lead to corrupted files.
66 gpfs:hsm = [ yes | no ]
69 Enable/Disable announcing if this FS has HSM enabled.
70 · no(default) - Do not announce HSM.
72 · yes - Announce HSM.
74 gpfs:recalls = [ yes | no ]
77 When this option is set to no, an attempt to open an offline file
78 will be rejected with access denied. This helps preventing recall
79 storms triggered by careless applications like Finder and Explorer.
80 · yes(default) - Open files that are offline. This will recall
82 the files from HSM.
83 · no - Reject access to offline files with access denied. This
85 will prevent recalls of files from HSM. Using this setting also
86 requires gpfs:hsm to be set to yes.
87 gpfs:getrealfilename = [ yes | no ]
90 Enable/Disable usage of the gpfs_get_realfilename_path() function.
91 This improves the casesensitive wildcard file name access.
92 · yes(default) - use gpfs_get_realfilename_path().
94 · no - do not use gpfs_get_realfilename_path(). It seems that
96 gpfs_get_realfilename_path() doesn´t work on AIX.
97 gpfs:winattr = [ yes | no ]
100 Enable/Disable usage of the windows attributes in GPFS. GPFS is
101 able to store windows file attributes e.g. HIDDEN, READONLY, SYSTEM
102 and others natively. That means Samba doesn´t need to map them to
103 permission bits or extended attributes.
104 · no(default) - do not use GPFS windows attributes.
106 · yes - use GPFS windows attributes.
108 gpfs:merge_writeappend = [ yes | no ]
111 GPFS ACLs doesn´t know about the ´APPEND´ right. This option lets
112 Samba map the ´APPEND´ right to ´WRITE´.
113 · yes(default) - map ´APPEND´ to ´WRITE´.
115 · no - do not map ´APPEND´ to ´WRITE´.
117 gpfs:acl = [ yes | no ]
120 This option lets Samba use or ignore GPFS ACLs.
121 · yes(default) - use GPFS ACLs.
123 · no - do not use GPFS ACLs and pass everything to the next
125 SMB_VFS module.
126 gpfs:refuse_dacl_protected = [ yes | no ]
129 As GPFS does not support the ACE4_FLAG_NO_PROPAGATE NFSv4 flag
130 (which would be the mapping for the DESC_DACL_PROTECTED flag), the
131 status of this flag is currently silently ignored by Samba. That
132 means that if you deselect the "Allow inheritable permissions..."
133 checkbox in Windows´ ACL dialog and then apply the ACL, the flag
134 will be back immediately.
135 To make sure that automatic migration with e.g. robocopy does not
137 lead to ACLs silently (and unintentionally) changed, you can set
138 gpfs:refuse_dacl_protected = yes to enable an explicit check for
139 this flag and if set, it will return NT_STATUS_NOT_SUPPORTED so
140 errors are shown up on the Windows side and the Administrator is
141 aware of the ACLs not being settable like intended
142 · no(default) - ignore the DESC_DACL_PROTECTED flags.
144 · yes - reject ACLs with DESC_DACL_PROTECTED.
146 gpfs:dfreequota = [ yes | no ]
149 Adjust reporting of the size and free space of a share according to
150 quotas. If this setting is "yes", a request for size and free space
151 will also evaluate the user quota of the user requesting the data,
152 the group quota of the primary group of the user and the fileset
153 quota for the fileset containing the top level directory of the
154 share.
155 If any of the soft or hard quota limits has been reached, the free
157 space will be reported as 0. If a quota is in place, but the limits
158 have not been reached, the free space will be reported according to
159 the space left in the quota. If more than one quota applies the
160 free space will be reported as the smallest space left in those
161 quotas. The size of the share will be reported according to the
162 quota usage. If more than one quota applies, the smallest size will
163 be reported for the share size according to these quotas.
164 · yes - include the quotas when reporting the share size and
166 free space
167 · no(default) - do not include quotas, simply report the size
169 and free space of the file system
170 gpfs:prealloc = [ yes | no ]
173 If set to yes the gpfs_prealloc function will be used in the
174 fallocate callback when appropriate. If set to no gpfs_prealloc
175 will not be used. In both cases the system and libc calls are
176 avoided.
177 · yes (default) - Use gpfs_prealloc for the fallocate callback.
179 · no - Do not use gpfs_prealloc for the fallocate callback.
181 gpfs:settimes = [ yes | no ]
184 Use the gpfs_set_times API when changing the timestamps of a file
185 or directory. If the GPFS API is not available the old method of
186 using utime and the GPFS winattr call will be used instead.
187 · yes(default) - Use gpfs_set_times. Fall back to utime and
189 winattr when it is not available.
190 · no - Do not use gpfs_set_times.
192 nfs4:mode = [ simple | special ]
195 Controls substitution of special IDs (OWNER@ and GROUP@) on GPFS.
196 The use of mode simple is recommended. In this mode only non
197 inheriting ACL entries for the file owner and group are mapped to
198 special IDs.
199 The following MODEs are understood by the module:
201 · simple(default) - use OWNER@ and GROUP@ special IDs for non
203 inheriting ACEs only.
204 · special(deprecated) - use OWNER@ and GROUP@ special IDs in ACEs
206 for all file owner and group ACEs.
207 nfs4:acedup = [dontcare|reject|ignore|merge]
210 This parameter configures how Samba handles duplicate ACEs
211 encountered in GPFS ACLs. GPFS allows/creates duplicate ACE for
212 different bits for same ID.
213 Following is the behaviour of Samba for different values :
215 · dontcare (default) - copy the ACEs as they come
217 · reject - stop operation and exit with error on ACL set op
219 · ignore - don´t include the second matching ACE
221 · merge - bitwise OR the 2 ace.flag fields and 2 ace.mask fields
223 of the 2 duplicate ACEs into 1 ACE
224 nfs4:chown = [yes|no]
227 This parameter allows enabling or disabling the chown supported by
228 the underlying filesystem. This parameter should be enabled with
229 care as it might leave your system insecure.
230 Some filesystems allow chown as a) giving b) stealing. It is the
232 latter that is considered a risk.
233 Following is the behaviour of Samba for different values :
235 · yes - Enable chown if as supported by the under filesystem
237 · no (default) - Disable chown
239 gpfs:syncio = [yes|no]
242 This parameter makes Samba open all files with O_SYNC. This
243 triggers optimizations in GPFS for workloads that heavily share
244 files.
245 Following is the behaviour of Samba for different values:
247 · yes - Open files with O_SYNC
249 · no (default) - Open files as normal Samba would do
251
254 A GPFS mount can be exported via Samba as follows :
255 [samba_gpfs_share]
257 vfs objects = gpfs
258 path = /test/gpfs_mount
259 nfs4: mode = special
260 nfs4: acedup = merge
261
263 Depending on the version of gpfs, the libgpfs_gpl library or the
264 libgpfs library is needed at runtime by the gpfs VFS module: Starting
265 with gpfs 3.2.1 PTF8, the complete libgpfs is available as open source
266 and libgpfs_gpl does no longer exist. With earlier versions of gpfs,
267 only the libgpfs_gpl library was open source and could be used at run
268 time.
269 At build time, only the header file gpfs_gpl.h is required, which is a
271 symlink to gpfs.h in gpfs versions newer than 3.2.1 PTF8.
272
274 This man page is correct for version 3.0.25 of the Samba suite.
275
277 The original Samba software and related utilities were created by
278 Andrew Tridgell. Samba is now developed by the Samba Team as an Open
279 Source project similar to the way the Linux kernel is developed.
280 The GPFS VFS module was created with contributions from Volker Lendecke
282 and the developers at IBM.
283 This manpage was created by the IBM FSCC team
285Samba 4.2 06/19/2018 VFS_GPFS(8)