The Registry path that contains entries for the Advanced Server file service is as follows:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
\AdvancedServer\FileServiceParameters
AclCacheSize REG_DWORD 0 - 100
Specifies the number of entries in ACL cache which keeps track of the results or recent access checks performed on Advanced Server resources.
Default: 6
EAFilePrefix REG_SZ Character string
Prefix used to name files containing extended attribute data. For example, by default, the extended attributes for file foo are stored in .ea@foo.
Default: .ea@
EnableSoftCompat REG_DWORD 0, 1, or 2
Specifies how Advanced Server handles file opens in read-only compatibility mode. Use 0 to keep the compatibility mode; 1 to translate to read-only/DenyWrite mode for files with special extensions (for example, .EXE, .COM, and .BAT) specified by the value of the EnableSoftFileExtensions key; and 2 to translate to read-only/DenyWrite mode for all file opens.
Default: 1 (translate files with special extensions to read-only/DenyWrite)
EnableSoftFileExtensions REG_MULTI_SZ List
Specifies the file extensions for which the compatibility mode will be translated to read-only/DenyWrite if the value of the EnableSoftCompat key is set to 1.
Default: bat com exe dll cmd
ForceDirectoryAcl REG_DWORD 0 or 1
Determines whether Advanced Server will create an access control list for a newly-created directory if an explicit access control list was not provided by the client computer. If an access control list is not created, one will be inherited automatically from its parent directory whenever it is needed.
Default: 1 (create new access control list)
Determines whether the Advanced Server will create an access control list for a newly-created file if an explicit access control list was not provided by the client computer. If an access control list is not created, one will be inherited automatically from its parent directory whenever it is needed.
Default: 0 (will not create new access control list)
ForceFileFlush REG_DWORD 0 or 1
Specifies whether to force a UNIX fsync(2) system call when an SMB flush request is received. Not forcing fsync(2) system calls can improve file server performance; files will be flushed automatically to disk by the UNIX fsflush daemon periodically, regardless of the setting of this key.
Default: 0 (will not force fsync system call)
IgnoreUnixPermissions REG_DWORD 0 or 1
Gives users the option to bypass UNIX system permissions when working with files and directories. For example, enabling this option would allow Advanced Server users to write to or delete files for which they have sufficient Advanced Server permissions even though only UNIX system read permissions had been granted to those files.
Default: 0 (enforce UNIX system permissions)
You can change the value of this key using the AS/U Administrator.
MappingSeparator REG_SZ Character string up to 7 characters
Specifies the string that will be appended to the file name before its unique suffix to indicate that the name is mapped. This value matters only in UNIX system to Windows NT file name mapping. The default is a tilde (~), the same as in UNIX system to 8.3 mapping, but it is possible to set it to enable the client to easily identify files containing characters illegal in Windows NT. By default, a file named "my?" will be mapped to "my_~xyz." When the value of this key is set to "~asu~", the name will be mapped to "my_~asu~xyz". If an invalid parameter is placed in the Registry, the MappingSeparator will be replaced by the default value.
Default: ~
You can change the value of this key using the AS/U Administrator.
MaxEASize REG_DWORD 1 - infinity
Specifies the buffer size in bytes that is allocated for extended attributes.
Default: 4096
MaxFileSizeInKB REG_DWORD 100 - infinity
The maximum file size, in KBytes, that Advanced Server will allow a user to create on the server.
Default: 20000
MemoryMapFiles REG_DWORD 0 or 1
Specifies whether the server uses the UNIX system mmap system call to memory map file data into the server's address space for efficiency. File mapping is attempted only for read-only files.
Default: 1 (memory map read-only files)
MixedCaseSupport REG_DWORD 0 or 1
Specifies whether mixed-case support is enabled on the server. Mixed-case support allows clients to access file names containing uppercase characters on the UNIX system. Enabling mixed-case support may negatively affect the server’s performance.
Default: 0 (make all file names lowercase)
You can change the value of this key using the AS/U Administrator.
NameSpaceMapping REG_DWORD 0, 1, 2, or 3
Specifies the type of file name space mapping enabled on the server.
A value of 0 indicates that there is no name space mapping enabled.
A value of 1 specifies that only UNIX system to 8.3 mapping is enabled. This allows 8.3-style clients, such as MS-DOS, Windows 3.1, and Windows for Workgroups, to access files with long file names and file names containing characters that are invalid in DOS ( + , ; = [ ] ? " \ < > * | : . [space] )
A value of 2 specifies that only UNIX system to Windows NT mapping is enabled. This allows Windows NT-style clients, such as Windows 95, Windows NT, and OS/2, to access files with file names containing characters that are illegal in Windows NT (? " \ < > * | :).
A value of 3 specifies that both UNIX system to 8.3 and UNIX system to Windows NT mappings are enabled.
Default: 3
You can change the value of this key using the AS/U Administrator.
OplockTimeout REG_DWORD 1 - infinity
The interval of time (in seconds) that the server waits for acknowledgment from a client of an "oplock" broken notification.
Default: 30
ReadAheadCount REG_DWORD 0 (always read ahead) - infinity
The number of sequential file accesses by a client that the server must detect before it begins reading ahead.
Default: 2
Specifies whether to report share UNIX system volumes as NTFS or actual UNIX file system type.
Default: 1 (report as NTFS)
RootOwnsFilesCreatedOnNFS REG_DWORD 0 or 1
Specifies whether files on NFS are owned by root or user.
Default: 0 (use files owned by the user’s UNIX system user ID)
You can change the value of this key using the AS/U Administrator.
SyncAclFileOnWrite REG_DWORD 0 or 1
Determines whether the server will force changes to the access control list (ACL) file to be written to disk using an fsync(2) system call or whether the server will permit the operating system to write the changes to disk normally.
Default: 0 (write ACL changes to disk normally)
TruncatedExtensions REG_DWORD 0 or 1
Specifies whether to replace the last character of the file extension of a mapped file name with a tilde (~). This key applies to file extensions which originally were longer than 3 characters. This feature can be used to distinguished longer file extensions from similar 3-character extensions that were unchanged. For example, enabling this feature prevents a file named file1.document from being mapped to a file named file~xyz.doc which could cause some clients to consider this file a Microsoft Word file. (This key affects only UNIX system to 8.3 file mapping.)
Default: 1 (Do not replace last character with a tilde.)
You can change the value of this key using the AS/U Administrator.
UniqueSuffixLength REG_DWORD 0 to 7
Specifies the length of the alpha-numeric suffix appended to the file name to guarantee the mapping uniqueness. The longer the suffix, the higher the probability that the mapped name is unique. If the mapped name is not unique within a directory, name collisions may occur. They may cause the client to be denied access to the file it needs, or the client may get access to a different file than the one it requested.
It is not advisable to set UniqueSuffixLength to a value less than 3, unless the preservation of a longer file name prefix outweighs possible name collision problems.
Default: 3
You can change the value of this key using the AS/U Administrator.
UnixCloseCount REG_DWORD 1 - 20
The number of least-recently accessed open files that the server closes transparently to avoid reaching the UNIX system’s per-process limit. The server uses a technique called file descriptor multiplexing to allow clients to open far more files than the per-process limits would normally allow.
Default: 5
UnixDirectoryCheck REG_DWORD 0, 1, or 2
Specifies whether Advanced Server will allow clients to write to UNIX system directories that do not have write permissions. Microsoft client software treats the "Read-Only" attribute as advisory and does not limit the behavior of directories. In contrast, the UNIX system treats "Read-Only" permissions as mandatory and prohibits users from writing in directories for which they do not have write permission.
A value of 0 allows writing only to directories with write permissions; a value of 1 allows writing to directories belonging to or created by Advanced Server (as determined by checking group memberships of directory); and a value of 2 ignores UNIX system directory permissions.
Default: 1
You can change the value of this key using the AS/U Administrator.
UnixDirectoryPerms REG_DWORD 0 - 511
The UNIX system permissions for newly-created directories.
Default: 509 (0775 octal)
You can change the value of this key using the AS/U Administrator.
UnixFilePerms REG_DWORD 0 - 4095
The UNIX system permissions for newly-created files.
Default: 1460 (02664 octal)
You can change the value of this key using the AS/U Administrator.
Specifies whether Advanced Server provides UNIX system disk quota support. This ensures that creating or writing to the file is performed under the UNIX system UID of the UNIX system user to which the Advanced Server user is mapped. Each action counts toward that user’s quota; an error message is sent to the client when the quota is exceeded. Two quotas are supported: i-node and block quotas for UFS and NFS file systems. This is true to the extent of the ability of these file systems to support UNIX system quotas.
Default: 0 (no support for disk quotas)
Specifies support for OS/2 extended attributes.
Default: 0 (no support for extended attributes)
Specifies whether the server tries to set UNIX system record locks in files as requested by clients. Record locks may not work on NFS files on a server running NFS. If the value of the UseUnixLocks key is 0, this feature has no effect on the server.
Default: 0 (do not set locks)
Specifies whether Advanced Server grants opportunistic locks to clients who request them on opens.
Default: 1 (use opportunistic locks)
Specifies whether record locks created by clients are reflected in the UNIX file system.
Default: 0 (locks are not reflected in UNIX file system)
You can change the value of this key using the AS/U Administrator.
Specifies whether physical UNIX system writes are performed before or after the server responds to the client. If UNIX system writes are performed before the server responds to the client, then the server appears to be slower (because the response is delayed), but the server can report disk full errors to clients. If UNIX system writes are performed after the response is sent, disk full errors during write SMBs are not reported to the client.
Default: 1 (enable write behind)