vfs_gpfs
8
Samba
System Administration tools
&doc.version;
vfs_gpfs
gpfs specific samba extensions like acls
vfs objects = gpfs
DESCRIPTION
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 makes use of the smb.conf parameter
.
When set to yes (the default), this parameter will add in the FILE_DELETE_CHILD
bit on a returned ACE entry for a file (not a directory) that already
contains all file permissions except for FILE_DELETE and FILE_DELETE_CHILD.
This can prevent Windows applications that request GENERIC_ALL access
from getting ACCESS_DENIED errors when running against a filesystem
with NFSv4 compatible ACLs.
This module is stackable.
Since Samba 4.0 all options are per share options.
OPTIONS
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:hsm = [ yes | no ]
Enable/Disable announcing if this FS has HSM enabled.
no(default) - Do not announce HSM.
yes - Announce HSM.
gpfs:recalls = [ yes | no ]
When this option is set to no, an attempt to
open an offline file will be rejected with access
denied. This helps preventing recall storms triggered
by careless applications like Finder and
Explorer.
yes(default) - Open
files that are offline. This will recall the files
from HSM.
no - Reject access
to offline files with access denied. This will prevent
recalls of files from HSM. Using this setting also
requires gpfs:hsm to be set to yes.
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:acl = [ yes | no ]
This option lets Samba use or ignore GPFS ACLs.
yes(default) - use GPFS ACLs.
no - do not use GPFS ACLs and pass everything
to the next SMB_VFS module.
gpfs:check_fstype = [ yes | no ]
Check for a mounted GPFS file system on access to a SMB share.
yes(default) - Check that the SMB share path
is on a GPFS file system. Share access will be denied when a
different file system is found.
no - skip check for GPFS file system on SMB
share path.
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.
gpfs:dfreequota = [ yes | no ]
Adjust reporting of the size and free space of a share
according to quotas. If this setting is "yes", a
request for size and free space will also evaluate the
user quota of the user requesting the data and the
group quota of the primary group of the user. Fileset
quotas are not queried, since GPFS already provides
the option --dfreequota to reflect the fileset quota
in the free space query. Please use that option to
include fileset quotas in the reported disk space.
If any of the soft or hard quota limits has been
reached, the free space will be reported as 0. If a
quota is in place, but the limits have not been
reached, the free space will be reported according to
the space left in the quota. If more than one quota
applies the free space will be reported as the smallest
space left in those quotas. The size of the share
will be reported according to the quota usage. If more
than one quota applies, the smallest size will be
reported for the share size according to these quotas.
yes - include the quotas
when reporting the share size and free space
no(default) - do not include quotas,
simply report the size and free space of the file system
gpfs:settimes = [ yes | no ]
Use the gpfs_set_times API when changing the
timestamps of a file or directory. If the GPFS API is
not available the old method of using utime and the
GPFS winattr call will be used instead.
yes(default) - Use gpfs_set_times.
Fall back to utime and winattr when it is not available.
no - Do not use gpfs_set_times.
nfs4:mode = [ simple | special ]
Controls substitution of special IDs (OWNER@ and GROUP@) on GPFS.
The use of mode simple is recommended.
In this mode only non inheriting ACL entries for the file owner
and group are mapped to special IDs.
The following MODEs are understood by the module:
simple(default) - use OWNER@ and GROUP@ special IDs for non inheriting ACEs only.
special(deprecated) - use OWNER@ and GROUP@ special IDs in ACEs for all file owner and group 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 - copy the ACEs as they come
reject (deprecated) - stop operation and exit with error on ACL set op
ignore (deprecated) - don't include the second matching ACE
merge (default) - 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
gpfs:syncio = [yes|no]
This parameter makes Samba open all files with O_SYNC.
This triggers optimizations in GPFS for workloads that
heavily share files.
Following is the behaviour of Samba for different
values:
yes - Open files with O_SYNC
no (default) - Open files as
normal Samba would do
EXAMPLES
A GPFS mount can be exported via Samba as follows :
gpfs
/test/gpfs_mount
special
merge
CAVEATS
Depending on the version of gpfs, the libgpfs_gpl
library or the libgpfs library is needed at
runtime by the gpfs VFS module:
Starting with gpfs 3.2.1 PTF8, the complete libgpfs
is available as open source and libgpfs_gpl does no
longer exist. With earlier versions of gpfs, only the
libgpfs_gpl library was open source and could be
used at run time.
At build time, only the header file gpfs_gpl.h
is required, which is a symlink to gpfs.h in
gpfs versions newer than 3.2.1 PTF8.
VERSION
This man page is part of version &doc.version; of the Samba suite.
AUTHOR
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