1VFS_GPFS(8) System Administration tools VFS_GPFS(8)
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6 vfs_gpfs - gpfs specific samba extensions like acls
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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.
43
45 nfs4:mode = [ simple | special ]
46 Controls substitution of special IDs (OWNER@ and GROUP@) on NFS4
47 ACLs. The use of mode simple is recommended. In this mode only non
48 inheriting ACL entries for the file owner and group are mapped to
49 special IDs.
50 The following MODEs are understood by the module:
52 • simple(default) - use OWNER@ and GROUP@ special IDs for
54 non inheriting ACEs only.
55 • special(deprecated) - use OWNER@ and GROUP@ special IDs
57 in ACEs for all file owner and group ACEs.
58 nfs4:acedup = [dontcare|reject|ignore|merge]
61 This parameter configures how Samba handles duplicate ACEs
62 encountered in NFS4 ACLs. They allow creating duplicate ACEs with
63 different bits for same ID, which may confuse the Windows clients.
64 Following is the behaviour of Samba for different values :
66 • dontcare - copy the ACEs as they come
68 • reject (deprecated) - stop operation and exit with error
70 on ACL set op
71 • ignore (deprecated) - don't include the second matching
73 ACE
74 • merge (default) - bitwise OR the 2 ace.flag fields and 2
76 ace.mask fields of the 2 duplicate ACEs into 1 ACE
77 nfs4:chown = [yes|no]
80 This parameter allows enabling or disabling the chown supported by
81 the underlying filesystem. This parameter should be enabled with
82 care as it might leave your system insecure.
83 Some filesystems allow chown as a) giving b) stealing. It is the
85 latter that is considered a risk.
86 Following is the behaviour of Samba for different values :
88 • yes - Enable chown if as supported by the under
90 filesystem
91 • no (default) - Disable chown
93 gpfs:sharemodes = [ yes | no ]
96 Enable/Disable cross node sharemode handling for GPFS.
97 • yes(default) - propagate sharemodes across all GPFS
99 nodes.
100 • no - do not propagate sharemodes across all GPFS nodes.
102 This should only be used if the GPFS file system is
103 exclusively exported by Samba. Access by local unix
104 application or NFS exports could lead to corrupted
105 files.
106 gpfs:leases = [ yes | no ]
109 Enable/Disable cross node leases (oplocks) for GPFS. You should
110 also set the oplocks and kernel oplocks options to the same value.
111 • yes(default) - propagate leases across all GPFS nodes.
113 • no - do not propagate leases across all GPFS nodes. This
115 should only be used if the GPFS file system is
116 exclusively exported by Samba. Access by local unix
117 application or NFS exports could lead to corrupted
118 files.
119 gpfs:hsm = [ yes | no ]
122 Enable/Disable announcing if this FS has HSM enabled.
123 • no(default) - Do not announce HSM.
125 • yes - Announce HSM.
127 gpfs:recalls = [ yes | no ]
130 When this option is set to no, an attempt to open an offline file
131 will be rejected with access denied. This helps preventing recall
132 storms triggered by careless applications like Finder and Explorer.
133 • yes(default) - Open files that are offline. This will
135 recall the files from HSM.
136 • no - Reject access to offline files with access denied.
138 This will prevent recalls of files from HSM. Using this
139 setting also requires gpfs:hsm to be set to yes.
140 gpfs:getrealfilename = [ yes | no ]
143 Enable/Disable usage of the gpfs_get_realfilename_path() function.
144 This improves the casesensitive wildcard file name access.
145 • yes(default) - use gpfs_get_realfilename_path().
147 • no - do not use gpfs_get_realfilename_path(). It seems
149 that gpfs_get_realfilename_path() doesn't work on AIX.
150 gpfs:winattr = [ yes | no ]
153 Enable/Disable usage of the windows attributes in GPFS. GPFS is
154 able to store windows file attributes e.g. HIDDEN, READONLY, SYSTEM
155 and others natively. That means Samba doesn't need to map them to
156 permission bits or extended attributes.
157 • no(default) - do not use GPFS windows attributes.
159 • yes - use GPFS windows attributes.
161 gpfs:acl = [ yes | no ]
164 This option lets Samba use or ignore GPFS ACLs.
165 • yes(default) - use GPFS ACLs.
167 • no - do not use GPFS ACLs and pass everything to the
169 next SMB_VFS module.
170 gpfs:check_fstype = [ yes | no ]
173 Check for a mounted GPFS file system on access to a SMB share.
174 • yes(default) - Check that the SMB share path is on a
176 GPFS file system. Share access will be denied when a
177 different file system is found.
178 • no - skip check for GPFS file system on SMB share path.
180 gpfs:dfreequota = [ yes | no ]
183 Adjust reporting of the size and free space of a share according to
184 quotas. If this setting is "yes", a request for size and free space
185 will also evaluate the user quota of the user requesting the data
186 and the group quota of the primary group of the user. Fileset
187 quotas are not queried, since GPFS already provides the option
188 --dfreequota to reflect the fileset quota in the free space query.
189 Please use that option to include fileset quotas in the reported
190 disk space.
191 If any of the soft or hard quota limits has been reached, the free
193 space will be reported as 0. If a quota is in place, but the limits
194 have not been reached, the free space will be reported according to
195 the space left in the quota. If more than one quota applies the
196 free space will be reported as the smallest space left in those
197 quotas. The size of the share will be reported according to the
198 quota usage. If more than one quota applies, the smallest size will
199 be reported for the share size according to these quotas.
200 • yes - include the quotas when reporting the share size
202 and free space
203 • no(default) - do not include quotas, simply report the
205 size and free space of the file system
206 gpfs:settimes = [ yes | no ]
209 Use the gpfs_set_times API when changing the timestamps of a file
210 or directory. If the GPFS API is not available the old method of
211 using utime and the GPFS winattr call will be used instead.
212 • yes(default) - Use gpfs_set_times. Fall back to utime
214 and winattr when it is not available.
215 • no - Do not use gpfs_set_times.
217 gpfs:syncio = [yes|no]
220 This parameter makes Samba open all files with O_SYNC. This
221 triggers optimizations in GPFS for workloads that heavily share
222 files.
223 Following is the behaviour of Samba for different values:
225 • yes - Open files with O_SYNC
227 • no (default) - Open files as normal Samba would do
229
232 A GPFS mount can be exported via Samba as follows :
233 [samba_gpfs_share]
235 vfs objects = gpfs
236 path = /test/gpfs_mount
237 nfs4: mode = special
238 nfs4: acedup = merge
239
241 Depending on the version of gpfs, the libgpfs_gpl library or the
242 libgpfs library is needed at runtime by the gpfs VFS module: Starting
243 with gpfs 3.2.1 PTF8, the complete libgpfs is available as open source
244 and libgpfs_gpl does no longer exist. With earlier versions of gpfs,
245 only the libgpfs_gpl library was open source and could be used at run
246 time.
247 At build time, only the header file gpfs_gpl.h is required, which is a
249 symlink to gpfs.h in gpfs versions newer than 3.2.1 PTF8.
250
252 This man page is part of version 4.18.9 of the Samba suite.
253
255 The original Samba software and related utilities were created by
256 Andrew Tridgell. Samba is now developed by the Samba Team as an Open
257 Source project similar to the way the Linux kernel is developed.
258 The GPFS VFS module was created with contributions from Volker Lendecke
260 and the developers at IBM.
261 This manpage was created by the IBM FSCC team
263Samba 4.18.9 11/30/2023 VFS_GPFS(8)