Understanding Oracle "LOG_ARCHIVE_START" parameter I've enabled ARCHIVELOG mode on a Oracle 12c multitenant instance: 


SQL> SELECT LOG_MODE FROM SYS.V$DATABASE;

LOG_MODE
------------
ARCHIVELOG


I understand that REDOLOGS are correctly archived by finding files in the configured path:


[root@LNXORA12 CSCONT01]# find ./ -type f
[...]
./archivelog/2017_03_22/o1_mf_1_5074_df3kfxmb_.arc
./archivelog/2017_03_22/o1_mf_1_5075_df417blj_.arc
./archivelog/2017_03_22/o1_mf_1_5076_df4bqqmf_.arc
./archivelog/2017_03_22/o1_mf_1_5077_df4q73mk_.arc
./archivelog/2017_03_22/o1_mf_1_5078_df4syvms_.arc
./archivelog/2017_03_22/o1_mf_1_5079_df4ttzs7_.arc
./archivelog/2017_03_22/o1_mf_1_5080_df501hrb_.arc
./archivelog/2017_03_22/o1_mf_1_5081_df57w8rj_.arc
./archivelog/2017_03_22/o1_mf_1_5082_df5gx2r5_.arc
./archivelog/2017_03_22/o1_mf_1_5083_df5mhsvj_.arc
./archivelog/2017_03_22/o1_mf_1_5084_df5sj5rx_.arc
./archivelog/2017_03_22/o1_mf_1_5085_df5sk6so_.arc
./archivelog/2017_03_22/o1_mf_1_5086_df5sq6sr_.arc
./archivelog/2017_03_22/o1_mf_1_5087_df5x4mto_.arc
./archivelog/2017_03_23/o1_mf_1_5088_df629bv9_.arc
./archivelog/2017_03_23/o1_mf_1_5089_df6ommvm_.arc
./archivelog/2017_03_23/o1_mf_1_5090_df73j2tt_.arc
[...]


Reading on many docs here and here the automatic archiving process is enabled only if LOG_ARCHIVE_START is set to TRUE but mine is set to FALSE.


SQL> select value from v$system_parameter where name = 'log_archive_start';

VALUE                                                                           
--------------------------------------------------------------------------------
FALSE                                                                           


Are my REDOLOGS really get archived?
First of all, the documentation that you have referenced are not from Oracle 12c, one is from Oracle 9i and another one is not the official documentation. 

Second of all, the parameter log_archive_start is deprecated in Oracle 10g, meaning no longer available in the next release. 


  Starting with Oracle Database 10g Release 1 (10.1), the LOG_ARCHIVE_START initialization parameter has been deprecated. Archiving is now automatically started when the database is placed in ARCHIVELOG mode.


Database Upgrade Guide 10g

Finally, You can use the following query to select all the deprecated parameters.

SQL&gt; SELECT name from v$parameter 
     WHERE isdeprecated = 'TRUE' ORDER BY name;


Documentation: Deprecated and Desupported Features