The DR is getting filled, or there are a lot of jobs that fail, or possibly less space than expected is being reported, or observed backup job performance is slower than expected
The cleaner has many functions. We recommend to read the Cleaner best practices on the support website for an insight on how to configure the Cleaner. https://support.quest.com/dr-series/dr4100/technical-documents
One of the most important aspects to running the Cleaner is time. A short description is that during a backup-job the data is sent to the DR, it is then queued for handling, like a Inbox. Then the Cleaner starts and looks over the data for duplicated information. What would happen after that is that the DR needs to compress the data that is stored. After compression the Cleaner starts to reclaim data before finally encrypting the volumes (if enabled). This can be viewed by using the CLI command:
The important number here is at the end of the output, "Estimated logical bytes left". This would indicate how large the workload is for the Cleaner at any given moment. The larger the number, the more time the system needs to reclaim space. Every job, replication, backup or reclamation, adds to the list of logical bytes. To check if the Cleaner is working, this number should always be decreasing, or be as close to 0 as possible. Please bear in mind that when savesets expire, the space is not reclaimed at first, reclamation is one of the last phases of the Cleaner tasks. Always wait until there is 0 bytes left to clean before evaluating the effectiveness.
If the estimated bytes left increases, this means that the Cleaner needs more time to handle the incoming jobs. There is a balance that needs to be found between running backups, then cleaning the data, then replicating data (if applicable). The larger the backup job (amount of data, or amount of clients) the more time needed for cleaning. It is recommended to not run any jobs while cleaning.
The Cleaner will not be able to reclaim all space that has been marked for deletion. To know how much data needs to be expired, first calculate the savings ratio. In the CLI, use this command:
At the end of the output "Total savings" is visible and this represents the duplication ratio. The space can be calculated like this: "Reclaimed space" approx "Expired data" * ((100 - "Total savings") / 100).
Following that example, calculating 1Tb data to be expired with a savings of 90% equalling approximately 100Gb of potential savings. This calculation is heavily depending on how much unique data has been stored. For example, if there is a full backup of a system that has little to no changes, it may be noticed that not much space is reclaimed at all. This would be normal.
The Cleaner can be run in three different modes: