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)