Oracle Database is running in No archive mode 


1> Update database parameter, log_archive_start, to value, TRUE

2> Shutdown database & middle tier processes

3> Start database using commands:

SQL>startup mount
SQL>alter database archivelog ;
SQL>alter database open;

4> Verify archivelog mode is enabled by running command

SQL>archive log list;

5> Start database listener & middle tier processes

6> Perform healthcheck