VBR v11 ūüĒ• How CDP Works with Retention Policies


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CDP - Retention Policies

 

A retention policy defines for how long Veeam Backup & Replication must store restore points for VM replicas. Veeam Backup & Replication offers two retention policy schemes:

:bulb:Long-term Retention

Veeam Backup & Replication retains long-term restore points for the number of days specified in CDP policy settings. When the retention period is exceeded, Veeam Backup & Replication transforms the replication chain in the following way. The example shows how long-term retention works for a VM replica with one virtual disk.

  1. Veeam Backup & Replication checks whether the replication chain contains outdated long-term restore points.
  2. If an outdated restore point exists, Veeam¬†Backup¬†&¬†Replication rebuilds the file that contains data for the base disk (<disk_name>-flat.vmdk) to include data of the file that contains data for the delta disk (<disk_name>-<index>.vmdk). To do that, Veeam¬†Backup¬†&¬†Replication commits into the base disk file data from the earliest delta disk file. This way, the base disk file ‚Äėmoves‚Äô forward in the replication chain

¬† ¬† ¬† ¬†3. Veeam¬†Backup¬†&¬†Replication removes the earliest delta disk file from the chain as redundant ‚ÄĒ¬† ¬† ¬† ¬† ¬† ¬† ¬† ¬†this data has already been commited into the base disk file.

                                           Retention Policies 

:triangular_flag_on_post:Short-term Retention

Veeam Backup & Replication retains short-term restore points for the number of hours specified in CDP policy settings. When the retention period is exceeded, Veeam Backup & Replication transforms the replication chain in the following way. The example shows how short-term retention works for a VM replica with one virtual disk.

  1. Veeam Backup & Replication checks whether the replication chain contains outdated short-term restore points.
  2. If an outdated restore point exists, Veeam Backup & Replication commints data for the restore point from the transaction log file (.tlog) into the nearest delta or base disk file (<disk_name>-flat.vmdk or <disk_name>-<index>.vmdk).
  3. If the transaction log file does not contain data for further restore points, Veeam¬†Backup¬†&¬†Replication deletes the transaction log file as redundant ‚ÄĒ its data has already been committed into the base or delta disk file.

NOTE

Veeam Backup & Replication can store short-term restore points for a longer period than specified in the short-term retention policy. This period is maximum 25% longer

 

 


2 comments

Userlevel 7
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Amazing work, thank you @eprieto !

Userlevel 6
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The CDP is surely the king of all features IMHO in v11. Hopefully, MS comes up with something like VAIO which can facilitate the same for HypervV.

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