Chapter 6

Creating and administering plexes

This chapter describes how to create and maintain plexes. Plexes are logical groupings of subdisks that create an area of disk space independent of physical disk size or other restrictions. Replication (mirroring) of disk data is set up by creating multiple data plexes for a single volume. Each data plex in a mirrored volume contains an identical copy of the volume data. Because each data plex must reside on different disks from the other plexes, the replication provided by mirroring prevents data loss in the event of a single-point disk-subsystem failure. Multiple data plexes also provide increased data integrity and reliability.

Note: Most VxVM commands require superuser or equivalent privileges.

Creating plexes

Note: Plexes are created automatically if you use the vxassist command or the Veritas Enterprise Administrator (VEA) to create volumes. For more information, see Creating a volume” on page 238.

Use the vxmake command to create VxVM objects, such as plexes. When creating a plex, identify the subdisks that are to be associated with it:

To create a plex from existing subdisks, use the following command:#vxmake [-gdiskgroup] plex plex sd=subdisk1[,subdisk2,...]

For example, to create a concatenated plex named vol01-02from two existing subdisks named mydg02-01and mydg02-02in the disk group, mydg, use the following command:

# vxmake -g mydg plex vol01-02 sd=mydg02-01,mydg02-02