Management Information Base
The DBMS server acts as a MIB Server.
MIB means Management Information Base, which in SNMP terms is a set of information in any system that can be monitored and manipulated for the purposes of system management.
From the standpoint of the monitoring application, the MIB is simply a set of tables in a relational database that can be queried and modified using SQL statements. In actuality, the MIB is an abstraction—it is composed of internal information spread among all the Ingres processes in an installation, including:
• The DBMS Server
• The archiver
• The recovery process
• The Name Server
• Communications servers
• Gateways
• Slave processes
The MIB server provides a central point of contact for the monitoring application, and acts as a distributed gateway to the actual MIB data, which in its natural habitat is not relational and does not reside in the same location.
The individual units of data are often referred to as “MIB objects” or “MIB variables” and most often are program variables in the code that runs the managed process.
A MIB object has a two-part name:
The object class
A generic variable type
An object instance
A unique identifier constructed for each actual manifestation of a MIB variable
Each object class also has a set of permissions defined for it that is used by the MIB server to enforce access control. This prevents unauthorized users from “playing” with the system.
Permissions are octal values:
For example:
• The class ID “exp.gcf.gca.trace_level” has a permission value of 28086, which is a decimal value. The octal value is 66666, which is:
MO_SES_READ + MO_SES_WRITE + MO_DBA_READ + MO_DBA_WRITE +
MO_SERVER_READ + MO_SERVER_WRITE + MO_SYSTEM_READ +
MO_SYSTEM_WRITE + MO_SECURITY_READ + MO_SECURITY_WRITE
• The class ID “exp.gwf.gwm.session.control.add_vnode” has a permission value of 6, which is a decimal value. The octal value is 6, which is:
MO_SES_READ + MO_SES_WRITE