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 is stackable.
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35 gpfs:sharemodes = [ yes | no ]
36 Enable/Disable cross node sharemode handling for GPFS.
37 · yes(default) - propagate sharemodes across all GPFS nodes.
39 · no - do not propagate sharemodes across all GPFS nodes. This
41 should only be used if the GPFS file system is exclusively
42 exported by Samba. Access by local unix application or NFS
43 exports could lead to corrupted files.
44 gpfs:leases = [ yes | no ]
47 Enable/Disable cross node leases (oplocks) for GPFS. You should
48 also set the oplocks and kernel oplocks options to the same value.
49 · yes(default) - propagate leases across all GPFS nodes.
51 · no - do not propagate leases across all GPFS nodes. This should
53 only be used if the GPFS file system is exclusively exported by
54 Samba. Access by local unix application or NFS exports could
55 lead to corrupted files.
56 gpfs:hsm = [ yes | no ]
59 Enable/Disable announcing if this FS has HSM enabled.
60 · no(default) - Do not announce HSM.
62 · no - Announce HSM.
64 gpfs:getrealfilename = [ yes | no ]
67 Enable/Disable usage of the gpfs_get_realfilename_path() function.
68 This improves the casesensitive wildcard file name access.
69 · yes(default) - use gpfs_get_realfilename_path().
71 · no - do not use gpfs_get_realfilename_path(). It seems that
73 gpfs_get_realfilename_path() doesn't work on AIX.
74 gpfs:winattr = [ yes | no ]
77 Enable/Disable usage of the windows attributes in GPFS. GPFS is
78 able to store windows file attributes e.g. HIDDEN, READONLY, SYSTEM
79 and others natively. That means Samba doesn't need to map them to
80 permission bits or extended attributes.
81 · no(default) - do not use GPFS windows attributes.
83 · yes - use GPFS windows attributes.
85 gpfs:merge_writeappend = [ yes | no ]
88 GPFS ACLs doesn't know about the 'APPEND' right. This optionen lets
89 Samba map the 'APPEND' right to 'WRITE'.
90 · yes(default) - map 'APPEND' to 'WRITE'.
92 · no - do not map 'APPEND' to 'WRITE'.
94 gpfs:refuse_dacl_protected = [ yes | no ]
97 As GPFS does not support the ACE4_FLAG_NO_PROPAGATE NFSv4 flag
98 (which would be the mapping for the DESC_DACL_PROTECTED flag), the
99 status of this flag is currently silently ignored by Samba. That
100 means that if you deselect the "Allow inheritable permissions..."
101 checkbox in Windows' ACL dialog and then apply the ACL, the flag
102 will be back immediately.
103 To make sure that automatic migration with e.g. robocopy does not
105 lead to ACLs silently (and unintentionally) changed, you can set
106 gpfs:refuse_dacl_protected = yes to enable an explicit check for
107 this flag and if set, it will return NT_STATUS_NOT_SUPPORTED so
108 errors are shown up on the Windows side and the Administrator is
109 aware of the ACLs not being settable like intended
110 · no(default) - ignore the DESC_DACL_PROTECTED flags.
112 · yes - reject ACLs with DESC_DACL_PROTECTED.
114 nfs4:mode = [ simple | special ]
117 Enable/Disable substitution of special IDs on GPFS. This parameter
118 should not affect the windows users in anyway. It only ensures that
119 Samba sets the special IDs - OWNER@ and GROUP@ ( mappings to simple
120 uids ) that are relevant to GPFS.
121 The following MODEs are understood by the module:
123 · simple(default) - do not use special IDs in GPFS ACEs
125 · special - use special IDs in GPFS ACEs.
127 nfs4:acedup = [dontcare|reject|ignore|merge]
130 This parameter configures how Samba handles duplicate ACEs
131 encountered in GPFS ACLs. GPFS allows/creates duplicate ACE for
132 different bits for same ID.
133 Following is the behaviour of Samba for different values :
135 · dontcare (default) - copy the ACEs as they come
137 · reject - stop operation and exit with error on ACL set op
139 · ignore - don't include the second matching ACE
141 · merge - bitwise OR the 2 ace.flag fields and 2 ace.mask fields
143 of the 2 duplicate ACEs into 1 ACE
144 nfs4:chown = [yes|no]
147 This parameter allows enabling or disabling the chown supported by
148 the underlying filesystem. This parameter should be enabled with
149 care as it might leave your system insecure.
150 Some filesystems allow chown as a) giving b) stealing. It is the
152 latter that is considered a risk.
153 Following is the behaviour of Samba for different values :
155 · yes - Enable chown if as supported by the under filesystem
157 · no (default) - Disable chown
159 gpfs:syncio = [yes|no]
162 This parameter makes Samba open all files with O_SYNC. This
163 triggers optimizations in GPFS for workloads that heavily share
164 files.
165 Following is the behaviour of Samba for different values:
167 · yesOpen files with O_SYNC
169 · no (default)Open files as normal Samba would do
171
174 A GPFS mount can be exported via Samba as follows :
175 [samba_gpfs_share]
177 vfs objects = gpfs
178 path = /test/gpfs_mount
179 nfs4: mode = special
180 nfs4: acedup = merge
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183 Depending on the version of gpfs, the libgpfs_gpl library or the
184 libgpfs library is needed at runtime by the gpfs VFS module: Starting
185 with gpfs 3.2.1 PTF8, the complete libgpfs is available as open source
186 and libgpfs_gpl does no longer exist. With earlier versions of gpfs,
187 only the libgpfs_gpl library was open source and could be used at run
188 time.
189 At build time, only the header file gpfs_gpl.h is required , which is a
191 symlink to gpfs.h in gpfs versions newer than 3.2.1 PTF8.
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194 This man page is correct for version 3.0.25 of the Samba suite.
195
197 The original Samba software and related utilities were created by
198 Andrew Tridgell. Samba is now developed by the Samba Team as an Open
199 Source project similar to the way the Linux kernel is developed.
200 The GPFS VFS module was created with contributions from Volker Lendecke
202 and the developers at IBM.
203 This manpage was created by the IBM FSCC team
205Samba 3.6 04/11/2016 VFS_GPFS(8)