The Snapshot Cleanup feature is responsible for removing old snapshots created by VASL product. It looks for snapshots, which had been created as part of SAP system provisioning through the adapter, but not removed due to unpreventable execution errors or failed operations. It is triggered every 48 hours and removes snapshots having live-time longer than 12 hours. It resets the countdown timer to the next cleanup run every time the VLA service has been restarted.
Figure 1. Example of snapshot taken by the adapter

The snapshots are deleted one at a time and VM-by-VM to minimize the number of simultaneous disk operations and the impact on other running vCenter tasks in a production environment.

Note: The service does not trigger a cleanup for a virtual machine if there are running disk operations, like
  • VM clone
  • Snapshot operations
  • Migrate operation
An attempt to remove stale snapshots of skipped virtual machines is made during the next run of the service.
The function is configurable by means of the vla_user_property script. Run the command with the ‘-l’ option to get information about available customizable properties:
# vla_user_property -l
The configurable attributes are:
  • enabled – turning on/off the feature
  • interval – a time period (in hours) between service runs. The range of allowed values is 4-744
  • lifetime – a maximum time (in hours) to keep snapshots taken by VASL. The range of allowed values is 4-744
Run the following command to see a current value of an attribute:
# vla_user_property -g -p <attribute name>
Run the following command to set a new value of an attribute:
# vla_user_property -s -p <attribute name> -v <new value>