NAME

       mkfs.gfs2 - Make a GFS2 filesystem

SYNOPSIS

       mkfs.gfs2 [OPTION]... DEVICE [ block-count ]

DESCRIPTION

       mkfs.gfs2 is used to create a Global File System.

OPTIONS

       -b BlockSize
              Set  the  filesystem block size to BlockSize (must be a power of two).  The minimum
              block size is 512.  The FS block size cannot exceed the machine's memory page size.
              On the most architectures (i386, x86_64, s390, s390x), the memory page size is 4096
              bytes.  On other architectures it may be bigger.  The default block  size  is  4096
              bytes.  In general, GFS2 filesystems should not deviate from the default value.

       -c MegaBytes
              Initial size of each journal's quota change file

       -D     Enable debugging output.

       -h     Print  out  a  help  message  describing  available options, then exit.

       -J MegaBytes
              The  size  of the journals in Megabytes. The default journal size is 128 megabytes.
              The minimum size is 8 megabytes.

       -j Number
              The number of journals for gfs2_mkfs to create.  You need at least one journal  per
              machine  that  will  mount  the  filesystem.   If this option is not specified, one
              journal will be created.

       -K     Keep, do not attempt to discard blocks at mkfs time (discarding blocks initially is
              useful on solid state devices and  sparse  /  thin-provisioned storage).

       -O     This  option  prevents  gfs2_mkfs  from  asking for confirmation before writing the
              filesystem.

       -o     Specify extended options. Multiple  options  can  be  separated  by  commas.  Valid
              extended options are:

                 help   Display an extended options help summary, then exit.

                 sunit=bytes
                        This  is  used  to  specify  the stripe unit for a RAID device or striped
                        logical volume.  This option ensures that resource groups will be  stripe
                        unit  aligned and overrides the stripe unit value obtained by probing the
                        device. This value must be a multiple of the file system block  size  and
                        must be specified with the swidth option.

                 swidth=bytes
                        This  is  used  to  specify the stripe width for a RAID device or striped
                        logical volume.  This option ensures that resource groups will be  stripe
                        aligned  and  overrides  the  stripe  width value obtained by probing the
                        device. This value must be a multiple of the sunit option and  must  also
                        be specified with it.

                 align=[0|1]
                        Disable or enable the alignment of resource groups. The default behaviour
                        is to align resource groups to the stripe width and  stripe  unit  values
                        obtained  from  probing the device or specified with the swidth and sunit
                        extended options.

       -p LockProtoName
              LockProtoName is the name of the  locking  protocol  to  use.   Acceptable  locking
              protocols  are  lock_dlm  (for  shared storage) or if you are using GFS2 as a local
              filesystem (1 node only), you can specify the lock_nolock protocol.  If this option
              is not specified, lock_dlm protocol will be assumed.

       -q     Be quiet.  Don't print anything.

       -r MegaBytes
              gfs2_mkfs  will  try to make Resource Groups about this big.  Minimum RG size is 32
              MB.  Maximum RG size is 2048 MB.  A large RG size may increase performance on  very
              large  file  systems.  If not specified, mkfs.gfs2 will choose the RG size based on
              the size of the file system: average size file systems will have 256  MB  RGs,  and
              bigger file systems will have bigger RGs for better performance.

       -t LockTableName
              The  lock  table  field  appropriate  to  the  lock  module  you're  using.   It is
              clustername:fsname.  Clustername must match that in cluster.conf; only  members  of
              this cluster are permitted to use this file system.  Fsname is a unique file system
              name used to distinguish this GFS2  file  system  from  others  created  (1  to  16
              characters).   Lock_nolock  doesn't  use this field. Valid clusternames and fsnames
              may only contain alphanumeric characters, hyphens (-) and underscores (_).

       -V     Print program version information, then exit.

       [ block-count ]
              Make the file system this many blocks in size.  If not specified, the entire length
              of the specified device is used.

EXAMPLE

       gfs2_mkfs -t mycluster:mygfs2 -p lock_dlm -j 2 /dev/vg0/mygfs2
              This will make a Global File System on the block device "/dev/vg0/mygfs2".  It will
              belong to "mycluster" and register itself as wanting locking for "mygfs2".  It will
              use DLM for locking and make two journals.

       gfs2_mkfs -t mycluster:mygfs2 -p lock_nolock -j 3 /dev/vg0/mygfs2
              This will make a Global File System on the block device "/dev/vg0/mygfs2".  It will
              belong to "mycluster" and  but  have  no  cluster  locking.   It  will  have  three
              journals.

                                                                                     mkfs.gfs2(8)