The glossary below contains many of the terms you will find in common use throughout the Symantec Security Response website. Please refer to this list to find definitions of terms and answers to other Internet security-related questions.

DRL Dirty Region Logging

A VxVM mechanism that tracks mirror write inconsistency, which helps in fast resynchronization of mirrors after system crash. Internally, DRL is implemented as a map and not as a log.

The method by which the VxVM monitors and logs modifications to a plex as a bitmap of changed regions. For volumes with a new-style DCO volume, the dirty region log is maintained in the DCO volume. Otherwise, the dirty region log is allocated to an associated subdisk called a log subdisk.

An optional property of a volume, used to provide a speedy recovery of mirrored volumes after a system failure. DRL keeps track of the regions that have changed due to I/O writes to a mirrored volume.