While performing the preinstallation tasks for an Oracle database on the AIX operating system, one of the requirements in the documentation asked that I “Ensure that the system is started with run level 2.” However these instructions did not show me how I should check this.
Simple Answer: who -r
The reason that AIX operating system needs to be at level 2, is that is the “Normal Multi-user mode which is its default”. This is to ensure that the operating system is not in a single user or restricted mode. The Linux operating systems may be at level 3. For more information, the following link is to the Wikipedia document on “Runlevel”.
The “who” command with the “-r” switch indicates the current run level.
> who -r