This article applies to:
Product edition: Phoenix
Problem description
SQL differential backup runs as full due to shrinking of database size.
Cause
The database is shrunk manually or the Shrink DB plan is running on the SQL Management Studio.
Traceback
2019-06-03 07:39:04,707] [INFO] <_MainThread(MainThread)> SQLBackup: Checking Backup Start Time [2019-06-03 07:39:04,707] [INFO] <_MainThread(MainThread)> Diff : ctxinfo = {'{a65faa63-5ea8-4ebc-9dbd-a0c4db26912a}': <roboClientLib.vssutils.Writer instance at 0x0000000003F7F508>} [2019-06-03 07:39:04,880] [INFO] <_MainThread(MainThread)> SQLBackup:, Checking for shrinked database files [2019-06-03 07:39:04,880] [INFO] <_MainThread(MainThread)> Checking for Shrink files for database [ABC_PQR_Aug07] of instance [AB3SERVER\AB3SERVER] [2019-06-03 07:39:04,881] [INFO] <_MainThread(MainThread)> Some of the databases are shrinked or blob database file has converted to block file, converting to full [2019-06-03 07:39:04,881] [INFO] <_MainThread(MainThread)> Disabled fault scheck for backup
Resolution
Verify whether the Shrink DB Maintenance plan is running on the SQL Management Studio.
If the plan is found running, remove the maintenance from the plan to ensure the differential backup does not run as full.
With regards to Shrink Database option, Microsoft suggests to avoid using the maintenance if database backup is already configured. Refer the limitations and restrictions specified by Microsoft from the See also section below.
After removing the Shrink Database maintenance plan, run the next backup. Subsequent backups run as defined.