ORA-01618: redo thread is not enabled – cannot mount

I got ” ORA-01618: redo thread is not enabled – cannot mount ” error in the Oracle database when i add new nodes to the Oracle RAC.

ORA-01618: redo thread is not enabled – cannot mount

Details of error are as follows.

SQL> startup
ORA-32004: obsolete or deprecated parameter(s) specified for RDBMS instance
ORACLE instance started.

Total System Global Area 2.6867E+11 bytes
Fixed Size 30150224 bytes
Variable Size 2.5770E+10 bytes
Database Buffers 2.4267E+11 bytes
Redo Buffers 207720448 bytes
ORA-01618: redo thread 3 is not enabled - cannot mount

redo thread 3 is not enabled – cannot mount

This ORA-01618 errors are related with the new node of Oracle RAC and missing thread and logfile of New added Oracle RAC Node.

I have added new 2 nodes to the Oracle RAC, Now We have 4 nodes RAC.

To solve this error, You need to enable the Node 3 and 4 Threads’ and Logfiles as follows.

SQL> alter database enable public thread 3;
alter database enable public thread 3
*
ERROR at line 1:
ORA-01613: instance UNNAMED_INSTANCE_3 (thread 3) only has 0 logs - at least 2
logs required to enable.


SQL> alter database enable public thread 4;
alter database enable public thread 4
*
ERROR at line 1:
ORA-01613: instance UNNAMED_INSTANCE_4 (thread 4) only has 0 logs - at least 2
logs required to enable.


SQL>

I got ORA-01613 error, because logfiles for the thread 3 and 4 should be added as follows.

SQL> alter database add logfile thread 3 group 11; 

Database altered.

SQL> alter database add logfile thread 3 group 12; 

Database altered. 

SQL> 

SQL> alter database add logfile thread 4 group 13; 

Database altered. 

SQL>

SQL> alter database add logfile thread 4 group 14; 

Database altered. 

SQL>

Now you can try to enable thread 3 and 4 as follows.

SQL> alter database enable public thread 3;

Database altered.

SQL> alter database enable public thread 4;

Database altered.

SQL>

Once you enabled the thread 3 and 4, you can startup the Node 3 and 4 as follows.

SQL> startup mount
ORACLE instance started.

Total System Global Area 2.6867E+11 bytes
Fixed Size 30150224 bytes
Variable Size 2.5770E+10 bytes
Database Buffers 2.4267E+11 bytes
Redo Buffers 207720448 bytes
Database mounted.
SQL>

If you want to learn more details about Oracle RAC Conversion, read the following post.

Convert Single Instance Oracle Database to Oracle RAC

Do you want to learn Oracle Database for Beginners, then read the following articles.

https://ittutorial.org/oracle-database-19c-tutorials-for-beginners/