Full and Differential Backup Phases

Each backup operation is composed of many backup phases that run in the background. These backup phases differ for each backup type. For example, backup phases that run during a first full backup is different from a subsequent full backup.

Before running a backup, you can change some settings in the backup phases, such as number of BLOBs processed per batch, number of disaster recovery run for delayed stubbing.

Backup Phases of the First Full Backup

The first full backup is composed of the following phases that run in the background sequentially.

Backup Phase Associated Activity
SharePoint Scan Obtains a list of Farm components including Storage Manager databases and BLOB locations to be backed up.
Full MSSQL Backup Runs a full backup operation on the SQL databases.
File System Scan Obtains the BLOB location from the SharePoint Scan phase and decides on the BLOBs to be backed up and stubbed.

By default, 1000 BLOBs are processed per batch during this phase. This number can be changed by setting a value for nRBSBatchCount. The value set for this additional setting indicates the number of BLOBs that is processed per batch.

File System Backup Backs up the BLOBs.
SharePoint Backup Backs up the web applications and other Farm components.
Archive Index Index cache for the backup job is backed up to the media.
Stubbing BLOBs that meet the archiving rules are delayed stubbed by 24 hours. For more details, refer to Delayed Stubbing.

Backup Phases of the Subsequent Full Backups

The subsequent full backups are composed of the following phases that run in the background sequentially.

Backup Phase Associated Activity
SharePoint Scan Obtains a list of Farm components including Storage Manager databases and BLOB locations to be backed up.
Full MSSQL Backup Runs a full backup operation on the SQL databases.
File System Synthetic Full Backup Runs a File System synthetic full backup for the BLOB location.
File System Scan Obtains the BLOB location from the SharePoint Scan phase and decides on the BLOBs to be backed up and stubbed.

By default, 1000 BLOBs are processed per batch during this phase. This number can be changed by setting a value for nRBSBatchCount. The value set for this additional setting indicates the number of BLOBs that is processed per batch.

File System Backup Backs up the BLOBs. This is a forever incremental phase.
SharePoint Backup Backs up the web applications and other Farm components.
Archive Index Index cache for the backup job is backed up to the media.
Stubbing BLOBs that meet the archiving rules are delayed stubbed by 24 hours. For more details, refer to Delayed Stubbing.

Backup Phases of Differential Backup

The differential backup is composed of the following phases that run in the background sequentially.

Backup Phase Associated Activity
SharePoint Scan Obtains a list of Farm components including Storage Manager databases and BLOB locations to be backed up.
Differential or Transaction Log MSSQL Backup
  • Runs a differential backup operation on SQL databases if the databases are set to simple recovery model.
  • Runs a transaction log backup operation on SQL databases if the databases are set to either a full recovery model or a bulk-logged recovery model.
File System Scan Obtains the BLOB location from the SharePoint Scan phase and decides on the BLOBs to be backed up and stubbed.

By default, 1000 BLOBs are processed per batch during this phase. This number can be changed by setting a value for nRBSBatchCount. The value set for this additional setting indicates the number of BLOBs that is processed per batch.

File System Backup Backs up the BLOBs. This is a forever incremental phase.
SharePoint Backup Backs up the web applications and other Farm components. 
Archive Index Index cache for the backup job is backed up to the media.
Stubbing BLOBs that meet the archiving rules are delayed stubbed by 24 hours. For more details, refer to Delayed Stubbing.