Appendix C

PCI Hot Plug

Introduction

PCI Hot Plug is a feature that allows a PCI card to be replaced while the host system is still running. The term “Hot Plug” is somewhat misleading; the PCI card cannot simply be pulled out of the host system while the card is operating without risk to the card, the system, and the data on the system.

In order to replace a Hot Plug PCI card, a software command must be invoked to power off the card slot before the card can be removed. After the software indicates that the card is unloaded and the slot is powered off, a physical card retainer/switch must be released to allow the card to be removed from the PCI bus. At this point, the card can be replaced.

At this time, Mylex only supports Hot Replacement of PCI Hot Plug cards. Future releases are planned to support Hot Upgrade or Hot Expansion (adding a card).

Implementation

Aside from the general terms previously mentioned, PCI Hot Plug implementation is specific to the host hardware platform and the operating system running on it. Refer to your host system's documentation for specific details on how to implement PCI Hot Plug.

NetWare

When NetWare is installed on a system capable of PCI Hot Plug, the following four modules are installed:

•cpqsbd.nlm - This is the Compaq system bus driver (a different driver will be needed for a platform other than Compaq).

•ncm.nlm - This is the Novell Configuration Manager, which manages the PCI Hot Plug system.

•ncmcon.nlm - This is the Hot Plug user interface called the Novell Configuration Manager Console.

Manual No. 775064

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