Creating volumes 259

Creating a volume using vxmake

If each column in a RAID-5 plex is to be created from multiple subdisks which may span several physical disks, you can specify to which column each subdisk should be added. For example, to create a three-column RAID-5 plex using six subdisks, use the following form of the vxmake command:

#vxmake -g mydg plex raidplex layout=raid5 stwidth=32 \ sd=mydg00-00:0,mydg01-00:1,mydg02-00:2,mydg03-00:0, \ mydg04-00:1,mydg05-00:2

This command stacks subdisks mydg00-00and mydg03-00consecutively in column 0, subdisks mydg01-00and mydg04-00consecutively in column 1, and subdisks mydg02-00and mydg05-00in column 2. Offsets can also be specified to create sparse RAID-5 plexes, as for striped plexes.

Log plexes may be created as default concatenated plexes by not specifying a layout, for example:

#vxmake -g mydg plex raidlog1 sd=mydg06-00#vxmake -g mydg plex raidlog2 sd=mydg07-00The following command creates a RAID-5 volume, and associates the preparedRAID-5 plex and RAID-5 log plexes with it:

#vxmake -g mydg -Uraid5 vol raidvol \ plex=raidplex,raidlog1,raidlog2

Note: Each RAID-5 volume has one RAID-5 plex where the data and parity are stored. Any other plexes associated with the volume are used as RAID-5 log plexes to log information about data and parity being written to the volume.

After creating a volume using vxmake, you must initialize it before it can be used.

The procedure is described in “Initializing and starting a volume” on page 260.Creating a volume using a vxmake description file

You can use the vxmake command to add a new volume, plex or subdisk to the set of objects managed by VxVM. vxmake adds a record for each new object to the VxVM configuration database. You can create records either by specifying parameters to vxmake on the command line, or by using a file which contains plain-text descriptions of the objects. The file can also contain commands for performing a list of tasks. Use the following form of the command to have vxmake read the file from the standard input:

#vxmake [-gdiskgroup] < description_fileAlternatively, you can specify the file to vxmake using the -doption:# vxmake [-g diskgroup] -d description_file