VxFS utilizes two types of volumes, one of which contains only data, referred to as dataonly, and the other of which can contain metadata or data, referred to as metadataok.
Data refers to direct extents, which contain user data, of regular files and named data streams in a file system.
Metadata refers to all extents that are not regular file or named data stream extents. This includes certain files that appear to be regular files, but are not, such as the File Change Log file.
A volume availability flag is set to specify if a volume is dataonly or metadataok. The volume availability flag can be set, cleared, and listed with the fsvoladm command.
fsvoladm(1M) manual page.