VxFS reduces system failure recovery times by tracking file system activity in the VxFS intent log. This feature records pending changes to the file system structure in a circular intent log. The intent log recovery feature is not readily apparent to users or a system administrator except during a system failure. During system failure recovery, the VxFS fsck utility performs an intent log replay, which scans the intent log and nullifies or completes file system operations that were active when the system failed. The file system can then be mounted without requiring a full structural check of the entire file system. Replaying the intent log may not completely recover the damaged file system structure if there was a disk hardware failure; hardware problems may require a complete system check using the fsck utility provided with VxFS.

The mount command automatically runs the VxFS fsck command to perform an intent log replay if the mount command detects a dirty log in the file system. This functionality is only supported on a file system mounted on a Veritas Volume Manager (VxVM) volume, and is supported on cluster file systems.

See The log option and data integrity.