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Enabling raw device access when creating a volume set

To enable raw device access when creating a volume set, use the following form of the vxvset make command:

# vxvset [-g diskgroup] -o makedev=on \

  [-o compvol_access={read-only|read-write}] \

  [-o index] [-c "ch_addopt"] make vset vol [index]

The -o makedev=on option enables the creation of raw device nodes for the component volumes at the same time that the volume set is created. The default is setting is off.

If the -o compvol_access=read-write option is specified, direct writes are allowed to the raw device of each component volume. If the value is set to read-only, only reads are allowed from the raw device of each component volume.

If the -o makedev=on option is specified, but -o compvol_access is not specified, the default access mode is read-only.

If the vxvset addvol command is subsequently used to add a volume to a volume set, a new raw device node is created in /dev/vx/rdsk/diskgroup if the value of the makedev attribute is currently set to on. The access mode is determined by the current setting of the compvol_access attribute.

The following example creates a volume set, myvset1, containing the volume, myvol1, in the disk group, mydg, with raw device access enabled in read-write mode:

# vxvset -g mydg -o makedev=on -o compvol_access=read-write \   make myvset1 myvol1