PCI Hot Plug Architecture

The PCI Hot Plug architecture is modular, which minimizes the changes required of third-party adapter software. The system relies on a central component, the Novell Event Bus (NEB), which facilitates communication among different software modules.

The NEB is an integral part of NetWare 5^TM. It is coded into the operating system so you never need to load the neb.nlm as a separate program.

Figure 1 provides a graphical representation of the NEB architecture.

Figure 1
Novell NetWare Hot Plug Architecture

Open Datalink Interface (ODI)

The Open Data-link Interface and the Novell Event Bus have been combined in one module, called odineb.nlm, to enable the NEB to control device drivers. The function of this module is to intercept requests to unload a device driver and ensure that the instance unload function is supported. It prevents false attempts to unload an unsupported driver and eliminates potential failures.

Novell Configuration Manager (ncm.nlm)

For PCI Hot Plug servers, the Novell Configuration Manager manages the Hot Plug system and ensures proper system behavior.

The primary function of the Configuration Manager is to sequence Hot Plug operations by shutting down the adapter's device driver before removing power from the slot. This ensures the stability of the system.

The Configuration Manager also maps hardware resources to device driver software.

System Bus Driver

The system bus driver is the platform-specific implementation of PCI Hot Plug. This driver controls the system hardware necessary to perform Hot Plug functions and is responsible for the following:

Enabling or removing power from a Hot Plug slot upon request.
Configuring hardware and assigning such things as memory, PCI, and interrupts of PCI adapters in Hot Plug slots.

NetWare allows multiple system bus driver modules to exist simultaneously. The controller manufacturer provides the system bus driver specific to the PCI Hot Plug hardware. The Compaq system bus driver, cpqsbd.nlm, is included with NetWare 5.

Novell Configuration Manager Console (ncmcon.nlm)

The Novell Configuration Manager console provides the interface for controlling all Hot Plug operations. In addition, it displays slot configuration details, including adapter driver information and status.

The Configuration Manager console consists of three screens: the Main Menu, Slot Options, and Slot Detailed Information.

The Novell Configuration Manager Console is described in detail in Introduction to NCMCON.