ORA-19751: could not create the change tracking file

Let’s make it simple to solve the problem:

# Error:

SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-19751: could not create the change tracking file
ORA-19750: change tracking file: '+DGDATA/mydb/changetracking/ctf.470.859997781'
ORA-17502: ksfdcre:1 Failed to create file +DGDATA/mydb/changetracking/ctf.470.859997781
ORA-17501: logical block size 4294967295 is invalid
ORA-15001: diskgroup "DGDATA" does not exist or is not mounted
ORA-17503: ksfdopn:2 Failed to open file +DGDATA/mydb/changetracking/ctf.470.859997781
ORA-15001: diskgroup "DGDATA" does not exist or is not mounted
ORA-15001: diskgroup "DGDATA" does not exist or is not mounted

# Solution:

SQL> alter database disable BLOCK CHANGE TRACKING;
Database altered.
SQL> alter database open;
Database altered.

Then, after everything be OK, you fix the situation recrating a BCTF:

ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE '+DGDATANEW';

MTFBWU!

Matheus.