SYNOPSIS

mkfs.gfs [OPTION]... DEVICE

DESCRIPTION

mkfs.gfs 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, GFS filesystems should not deviate from the default value.

-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 32 megabytes.

-j Number

The number of journals for mkfs.gfs to create. You need at least one journal per machine that will mount the filesystem.

-O

This option prevents mkfs.gfs from asking for confirmation before writing the filesystem.

-p LockProtoName

LockProtoName is the name of the locking protocol to use. The locking protocol should be lock_dlm for a clustered file system or if you are using GFS as a local filesystem (1 node only), you can specify the lock_nolock protocol.

-q

Be quiet. Don't print anything.

-r MegaBytes

mkfs.gfs will try to make Resource Groups (RGs) 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.gfs 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.

-s Blocks

Journal segment size in filesystem blocks. This value must be at least two and not large enough to produce a segment size greater than 4MB.

-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 GFS file system from others created (1 to 16 characters). Lock_nolock doesn't use this field.

-V

Print program version information, then exit.

EXAMPLE

mkfs.gfs -t mycluster:mygfs -p lock_dlm -j 2 /dev/vg0/mygfs

This will make a Global File System on the block device "/dev/vg0/mygfs". It will belong to "mycluster" and register itself as wanting locking for "mygfs". It will use DLM for locking and make two journals.