sammkfs(1M)

NAME
     sammkfs, samfsinfo - Constructs or displays information for
     a Sun QFS or SAM-QFS file system

SYNOPSIS
     /opt/SUNWsamfs/sbin/sammkfs [-a allocation_unit] [-i inodes]
     [-A] [-P] [-S] [-V] fs_name

     /opt/SUNWsamfs/sbin/samfsinfo fs_name

AVAILABILITY
     SUNWqfs

     SUNWsamfs

DESCRIPTION
     The sammkfs command creates a Sun QFS or SAM-QFS file system
     from the disk partitions that belong to the family set
     fs_name, where fs_name is the family set name as defined in
     the mcf file.  Up to 252 disk partitions can be specified in
     the mcf file for a Sun QFS or SAM-QFS file system.  The
     sammkfs command can also be used to recreate a file system
     after a disaster.

     The sammkfs command can create either a version 2 file
     system that is backwards compatible with previous releases,
     or a version 2A file system that has new features, but is
     not compatible with previous releases.  By default, a
     version 2A file system is created.  See -P parameter below
     for details on the new features, and how to create a version
     2 file system.

     The sammkfs command aligns the block allocation bit maps and
     round robins them on the metadata devices for improved
     performance.  This behavior is  backwards compatible with
     previous releases.  The option feature Aligned Maps is set.

     The samfsinfo command displays the structure of an existing
     Sun QFS or SAM-QFS file system.  The output is similar to
     that obtained by using the -V option to the sammkfs command.

OPTIONS
     These commands accept the following options:

     -a allocation_unit
               Specifies the disk allocation unit (DAU).  The DAU
               is the basic unit of online storage.  When you
               specify a DAU size, you specify the number of
               1024-byte (1 kilobyte) blocks to be allocated for
               a file.

               The DAU size you can specify depends on the type
               of file system being initialized, as follows:

               o  The SAM-QFS file system is an ms file system.
                  The disk devices in it are all md devices.
                  Both data and metadata are written to the md
                  devices.  The allocation_unit specifies the DAU
                  to be used for the md devices.  Possible
                  allocation_unit specifications are 16, 32, or
                  64 (the default).

               o  The Sun QFS or SAM-QFS file systems are ma file
                  systems.  The metadata in these file systems is
                  written to mm devices.  The disk devices in
                  these file systems are specified as either md,
                  mr, or gXXX devices, as follows:

                  -  For the md devices, possible allocation_unit
                     specifications are 16, 32, or 64 (the
                     default).  A single file system cannot have
                     md devices mixed among the mr and gXXX
                     devices.

                  -  For mr devices, the DAU is fully adjustable.
                     Specify an allocation_unit that is a
                     multiple of 8 in the following range for mr
                     devices:  8 < allocation_unit < 65528.  The
                     default is 64.

                  -  For gXXX devices, which specify striped
                     groups, the DAU is fully adjustable.  If the
                     file system contains striped groups, the
                     minimum unit of disk space allocated is the
                     DAU multiplied by the number of members in
                     the striped group.  Specify an
                     allocation_unit that is a multiple of 8 in
                     the following range for gXXX devices:
                     8 < allocation_unit < 65528.  The default is
                     256.

                  You can mix mr and gXXX devices in a single Sun
                  QFS or SAM-QFS file system.  If these device
                  types are mixed, the allocation_unit specified
                  is used for both device types.  If no
                  allocation_unit is specified, the DAU size used
                  for each type of device is 256.

     -i inodes Specifies the number of inodes to be allocated for
               this file system.  This is the total number of
               user inodes that can be used for the life of this
               file system. In Sun QFS and SAM-QFS version 2
               superblock file systems, a number of inodes are
               reserved for file system usage, and are
               unavailable to the user. This number is in
               addition to the specified number of user inodes.
               The actual number of inodes available vary from
               that specified, due to rounding to metadata DAU
               size.

               NOTE:  By specifying this option, you eliminate
               the possibility of ever increasing the number of
               inodes for the file system.  Therefore, Sun does
               not recommend the use of this option.

               When this option is specified, later use of the
               samgrowfs(1M) command increases the size of the
               file system, but it cannot increase the number of
               allowable inodes.  For more information on
               enlarging file systems, see the WARNINGS section
               of this man page and the samgrowfs(1M) man page.

     -A        Uses NFSv4 ACL style for the filesystem ACLs
               instead of POSIX ACL style. This feature is
               available only in releases of Solaris beyond
               Solaris 10.

     -P        Specifies that a previous version of the file
               system be created.  This version creates a version
               2 superblock and is compatible with SAM-QFS
               version 4.6.  This version cannot use the
               following features however:  large host table,
               extended attributes, and online grow.  Without the
               -P parameter, a version 2A superblock is created,
               the above features are available, and the file
               system is not usable with SAM-QFS version 4.6 or
               previous.

     -S        Indicates that this file system is shared.  In
               order to mount the file system as a Sun QFS shared
               file system, you must also create a hosts.fs_name
               configuration file.  For more information on this
               configuration file and other aspects of the Sun
               QFS shared file system, see the Sun QFS File
               System Configuration and Administration Guide.
               For information on configuring a hosts file, see
               the hosts.fs(4) man page.

     -V        Writes configuration information to standard
               output but does not execute the sammkfs command.
               This information can be used to create a new file
               system.

               The samfsinfo command should be used to generate
               configuration information for an existing file
               system.

EXAMPLES
     Example 1.  The following command creates SAM-QFS file
     system with a DAU size of 128 kilobytes:

     server#  sammkfs -a 128 samfs1

FILES
     /etc/opt/SUNWsamfs/mcf   The configuration file for a Sun
                              QFS or SAM-QFS file system

WARNINGS
     As with creating any type of file system, if you specify the
     wrong partition names, you risk damaging user or system
     data.  Be sure to specify partitions that are otherwise
     unused on your system.  Do not use overlapping partitions.

     With SAM-QFS 4.1 and greater AND Solaris 64bit kernels which
     support large disk devices (greater than 1 TB), it is
     possible to have partitions that are greater than 1 TB. Note
     that these file systems are not usable on Solaris systems
     that do not support large disk devices.

SEE ALSO
     dd(1M), samd(1M), samgrowfs(1M), undamage(1M).
     mcf(4).
     Sun QFS File System Configuration and Administration Guide.
     Sun Storage Archive Manager Configuration and Administration
     Guide.

WARNINGS
     Be careful when using the -i inodes option for this command.
     By using this option, you dictate the maximum number of
     inodes allowed for the life of this file system.  This
     eliminates the possibility of ever using the samgrowfs(1M)
     command to increase the number of files in this file system.
     After a file system is made with -i specified, the
     samgrowfs(1M) command can only be used to increase the size
     of the file system in terms of bytes.

NOTES
     Data alignment refers to matching the allocation unit of the
     RAID controller with the allocation_unit of the file system.
     A mismatched alignment causes a read-modify-write operation
     for I/O that is less than the block size.  The optimal
     alignment formula is as follows:
     allocation_unit = RAID_stripe_width * number_of_data_disks

     For example, if a RAID-5 unit has a total of 8 disks with 1
     of the 8 being the parity disk, the number of data disks is
     7.  If the RAID stripe width is 64 kilobytes, then the
     optimal allocation_unit is 64 * 7 = 448.