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LOCK_SGA=TRUE Causes An ORA-27126 During Database Startup On AIX (Doc ID 827656.1)

Last updated on JANUARY 29, 2024

Applies to:

Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
IBM AIX on POWER Systems (64-bit)
IBM AIX Based Systems (64-bit)
Fox Technologies BoKs


Having implemented the Fox Technologies BoKs product and environment variable LOCK_SGA=TRUE set, a Oracle database fails to start with error
  ORA-27126: unable to lock shared memory segment in core

This problem only affects Oracle on the AIX operating system.

Other symptoms include:

1) Previous versions of the Oracle 10.2 database did not experience this condition. Most customers so far see this issue after upgrading from

2) The version of AIX does not seem to matter either but most customers are on either AIX 5.3 or 6.1.

3) When customers use the truss command on the sqlplus session, they see and Err#1 EPERM on the shmctl() system call.

4) So far, all customers seeing this error condition are using a 3rd party security tool called BoKs from Fox Technologies. The customer can determine if they are using this product by looking for a line in /etc/inittab similar to:

rcboks:2:wait:/etc/rc.boks > /dev/console 2>&1 # Start BoKS 6.5

It may not match this exactly, but one only needs to search /etc/inittab on the string "boks" to find it.

5) Other security tools that customers have used such as powerbroker or SeOS do not display this problem.

6) Customers have asked Oracle development what has changed in shared memory allocation between and and the only code changes noticed where the use of vmgetinfo() system call before the shmget() / shmctl(). According to IBM, the vmgetinfo() system call should not require any special privileges or access permissions.


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