Solution for semaphores to allow more process while starting Oracle Database.

In this solution let us see how to increase the value of the semaphore in Linux for increasing the processes while we try to start the Oracle multi-instances.

ORA-27154: post/wait create failed
ORA-27300: OS system dependent operation:semget failed with status: 28
ORA-27301: OS failure message: No space left on device
ORA-27302: failure occurred at: sskgpcreates

To change the value of the semaphore we can perform by editing the below file.

# vi /etc/sysctl.conf

kernel.sem = 250 32000 100 428

semaphores Value has been configured to take effect we need to run

# sysctl -p

That’s it we can now start the Oracle Database instances by avoiding above error.