ORA-27300: OS system dependent operation:semget failed with status: 28

Found this error when creating a 10.2.0.3 database on solaris 9.

This error can occur on any unix host when starting an oracle database. The error is saying that the semiphore parameters are not set correctly.

In cases like this, the first parameter to look for is SEMMNS

Essentially this parameter tells how many os processes shared memory components can use on the server. So the important oracle database parameter to look at is process.

Use the following calulation to work out what SEMMNS should be set to:

SEMMNS = sum(oracle processes) + num oracle databases + system requirements

This all suggests when setting up a new server you should have an idea of the number of databases running on the server or set the SEMMNS parameter to a fairly high number.