The warning might be reported while running a backup for a VMware VADP backup set ( Linux DS-Client ).
1. The backup set has enabled the option "Attempt to use Change Block Tracking for backing up Virtual Machines" and the connection to the DS-System has been lost during backup, when the connection to the DS-System is re-established and the backup resumes ( or when a new backup session starts at the next scheduled time ), the DS-Client needs to read the whole vmdk so that it correctly captures the CBT info.
2. The VMware VADP backup set (Linux DS-Client) has the "local storage" option enabled and the hot fix 16 for Linux DS-Client v.12.2 SP1 has not been applied.
Apply the most recent Linux DS-Client hot fix for the Asigra version used.