vfs_gpfs 8 Samba System Administration tools 3.6 vfs_gpfs gpfs specific samba extensions like acls and prealloc vfs objects = gpfs This VFS module is part of the samba 7 suite. The gpfs VFS module is the home for all gpfs extensions that Samba requires for proper integration with GPFS. It uses the GPL library interfaces provided by GPFS. Currently the gpfs vfs module provides extensions in following areas : NFSv4 ACL Interfaces with configurable options for GPFS Kernel oplock support on GPFS Lease support on GPFS NOTE:This module follows the posix-acl behaviour and hence allows permission stealing via chown. Samba might allow at a later point in time, to restrict the chown via this module as such restrictions are the responsibility of the underlying filesystem than of Samba. This module is stackable. gpfs:sharemodes = [ yes | no ] Enable/Disable cross node sharemode handling for GPFS. yes(default) - propagate sharemodes across all GPFS nodes. no - do not propagate sharemodes across all GPFS nodes. This should only be used if the GPFS file system is exclusively exported by Samba. Access by local unix application or NFS exports could lead to corrupted files. gpfs:leases = [ yes | no ] Enable/Disable cross node leases (oplocks) for GPFS. You should also set the oplocks and kernel oplocks options to the same value. yes(default) - propagate leases across all GPFS nodes. no - do not propagate leases across all GPFS nodes. This should only be used if the GPFS file system is exclusively exported by Samba. Access by local unix application or NFS exports could lead to corrupted files. gpfs:getrealfilename = [ yes | no ] Enable/Disable usage of the gpfs_get_realfilename_path() function. This improves the casesensitive wildcard file name access. yes(default) - use gpfs_get_realfilename_path(). no - do not use gpfs_get_realfilename_path(). It seems that gpfs_get_realfilename_path() doesn't work on AIX. gpfs:winattr = [ yes | no ] Enable/Disable usage of the windows attributes in GPFS. GPFS is able to store windows file attributes e.g. HIDDEN, READONLY, SYSTEM and others natively. That means Samba doesn't need to map them to permission bits or extended attributes. no(default) - do not use GPFS windows attributes. yes - use GPFS windows attributes. gpfs:merge_writeappend = [ yes | no ] GPFS ACLs doesn't know about the 'APPEND' right. This optionen lets Samba map the 'APPEND' right to 'WRITE'. yes(default) - map 'APPEND' to 'WRITE'. no - do not map 'APPEND' to 'WRITE'. gpfs:refuse_dacl_protected = [ yes | no ] As GPFS does not support the ACE4_FLAG_NO_PROPAGATE NFSv4 flag (which would be the mapping for the DESC_DACL_PROTECTED flag), the status of this flag is currently silently ignored by Samba. That means that if you deselect the "Allow inheritable permissions..." checkbox in Windows' ACL dialog and then apply the ACL, the flag will be back immediately. To make sure that automatic migration with e.g. robocopy does not lead to ACLs silently (and unintentionally) changed, you can set gpfs:refuse_dacl_protected = yes to enable an explicit check for this flag and if set, it will return NT_STATUS_NOT_SUPPORTED so errors are shown up on the Windows side and the Administrator is aware of the ACLs not being settable like intended no(default) - ignore the DESC_DACL_PROTECTED flags. yes - reject ACLs with DESC_DACL_PROTECTED. nfs4:mode = [ simple | special ] Enable/Disable substitution of special IDs on GPFS. This parameter should not affect the windows users in anyway. It only ensures that Samba sets the special IDs - OWNER@ and GROUP@ ( mappings to simple uids ) that are relevant to GPFS. The following MODEs are understood by the module: simple(default) - do not use special IDs in GPFS ACEs special - use special IDs in GPFS ACEs. nfs4:acedup = [dontcare|reject|ignore|merge] This parameter configures how Samba handles duplicate ACEs encountered in GPFS ACLs. GPFS allows/creates duplicate ACE for different bits for same ID. Following is the behaviour of Samba for different values : dontcare (default) - copy the ACEs as they come reject - stop operation and exit with error on ACL set op ignore - don't include the second matching ACE merge - bitwise OR the 2 ace.flag fields and 2 ace.mask fields of the 2 duplicate ACEs into 1 ACE nfs4:chown = [yes|no] This parameter allows enabling or disabling the chown supported by the underlying filesystem. This parameter should be enabled with care as it might leave your system insecure. Some filesystems allow chown as a) giving b) stealing. It is the latter that is considered a risk. Following is the behaviour of Samba for different values : yes - Enable chown if as supported by the under filesystem no (default) - Disable chown A GPFS mount can be exported via Samba as follows : gpfs /test/gpfs_mount special merge The gpfs gpl libraries are required by gpfs VFS module during both compilation and runtime. Also this VFS module is tested to work on SLES 9/10 and RHEL 4.4 This man page is correct for version 3.0.25 of the Samba suite. The original Samba software and related utilities were created by Andrew Tridgell. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed. The GPFS VFS module was created with contributions from Volker Lendecke and the developers at IBM. This manpage was created by the IBM FSCC team