"Translated from MoS article" in Oracle DB 12c, Alert_sid.log permissions are changed each time the log is toggled

12c, each log switch will change the permissions of Alert_sid.log

From:
Alert log file ' s permissions change with every log switch in 12c (Doc ID 1637367.1)

Suitable for:
Oracle database-enterprise edition-version 12.1.0.1 and later
Information in this document applies to any platform.

Symptoms:

When trying to set the group write bit in the OS Permissions for the alert log file it gets reset after every log switchfo R Example:[[email protected] trace]$ pwd/u01/app/oracle/diag/rdbms/orcl/orcl/trace[[email protected] trace]$ LS-LRT ALERT_ORCL.LOG-RW-R-----1 Oracle Oinstall 357531 may  2 07:30 alert_orcl.log---> Right now 640[[email protected] Trac e]$--modified to 666[[email protected] trace]$ chmod 666 alert_orcl.log[[email protected] trace]$ LS-LRT ALERT_ORCL.LOG-RW-RW-RW -1 Oracle Oinstall 357988 may  2 07:42 alert_orcl.log---> Permissions for 666--log switchover sql> alter system switch logfile; System altered.--Check Permissions again [[email protected] trace]$ LS-LRT alert_orcl.log-rw-r--rw-1 Oracle Oinstall 358240 may  2 07: Alert_orcl.log---> Permissions at this time are 646[[email protected] trace]$

Reason:

This is a expected behavior, if it is required to has the group write bit set for the alert log and then group write bit NE EDS to is set for in the ADR home directory.

Solution:

chmod 770/<sid>/diag/rdbms/<sid>/<sid> then restart the database

"Translated from MoS article" in Oracle DB 12c, Alert_sid.log permissions are changed each time the log is toggled