Block Change Tracking (BCT) is a valuable Oracle feature that speeds up incremental RMAN backups by tracking changed blocks. However, after certain recovery operations or storage issues, the database may fail to open because Oracle cannot access or recreate the Block Change Tracking file.
In this article, we’ll look at the ORA-19751 error, understand why it occurs, and walk through the steps to resolve it safely.
Problem
While opening the database with RESETLOGS, Oracle returned the following error:
SQL> ALTER DATABASE OPEN RESETLOGS;
*
ERROR at line 1:
ORA-19751: could not create the change tracking file
ORA-19750: change tracking file:
'+DATAC1/PRIME_X9/CHANGETRACKING/ctf.3890.1233220197'
ORA-17502: ksfdcre:4 Failed to create file
ORA-15046: ASM file name '+DATAC1/PRIME_X9/CHANGETRACKING/ctf.3890.1233220197'
is not in single-file creation form
ORA-17503: ksfdopn:2 Failed to open file
ORA-15012: ASM file '+DATAC1/PRIME_X9/CHANGETRACKING/ctf.3890.1233220197' does not exist
Cause
This error occurs because Oracle attempts to access the existing Block Change Tracking (BCT) file during database startup.
Common reasons include:
- The BCT file has been deleted from ASM.
- ASM disk group changes caused the file to become inaccessible.
- The BCT file contains an invalid ASM alias.
- Database recovery or cloning left an invalid Block Change Tracking file reference.
- After
OPEN RESETLOGS, Oracle cannot recreate the existing BCT file automatically.
Since the BCT file is not required for database operation, the database can be opened by temporarily disabling Block Change Tracking.
Solution
Step 1 – Disable Block Change Tracking
SQL> ALTER DATABASE DISABLE BLOCK CHANGE TRACKING;
Database altered.
Step 2 – Open the Database
SQL> ALTER DATABASE OPEN;
Database altered.
The database should now open successfully.
Step 3 – Re-enable Block Change Tracking
If you use RMAN incremental backups, recreate the Block Change Tracking file after confirming the database is operating normally.
SQL> ALTER DATABASE ENABLE BLOCK CHANGE TRACKING
USING FILE '+DATA';
Database altered.
Oracle will create a new Block Change Tracking file in the specified ASM disk group.
Verify Block Change Tracking
Check the current status:
SELECT STATUS, FILENAME
FROM V$BLOCK_CHANGE_TRACKING;
Example output:
STATUS FILENAME
-------- ----------------------------------------
ENABLED +DATA/DBNAME/CHANGETRACKING/ctf....
Why This Works
When Block Change Tracking is enabled, Oracle expects the tracking file to exist and be accessible.
If the file is missing or invalid, the database may fail to open after recovery or RESETLOGS.
By disabling Block Change Tracking:
- Oracle removes the dependency on the missing file.
- The database opens normally.
- A new Block Change Tracking file can be created afterward.
Best Practices
- Always verify the Block Change Tracking status after recovery.
- Re-enable Block Change Tracking if you rely on RMAN incremental backups.
- Use only the ASM disk group name (for example,
+DATA) when recreating the file. Oracle will automatically generate the correct file name. - Avoid manually specifying ASM-generated file names such as:
+DATA/DBNAME/CHANGETRACKING/ctf.xxxxx.xxxxx
Conclusion
The ORA-19751: could not create the change tracking file error is commonly encountered after database recovery, cloning, or ASM storage changes. Since the Block Change Tracking file is not essential for opening the database, the quickest solution is to disable Block Change Tracking, open the database successfully, and then recreate the tracking file if RMAN incremental backups are required.
Following this approach restores database availability while ensuring backup performance can be maintained by re-enabling Block Change Tracking afterward.



