Novell NetWare 6.5 aacraid.ham driver is slow to load - IBM ServeRAID-8x

Resolving The Problem

Source

RETAIN tip: H192203

Issue

The ServeRAID-8 series controller device driver, AACRAID.HAM for Novell 6.5 takes about four to five minutes to load while starting the operating system. After the device driver loads, the device driver and operating system runs normally.

Affected configurations

This tip is not hardware specific.

The system is configured with one or more of the following IBM Options:

• ServeRAID-8i Controller, Option 13N2227, replacement part number 13N2233
• ServeRAID-8k SAS Controller, Option 25R8064, replacement part number 25R8076
• ServeRAID-8k-l SAS Controller, Option 39R8729, replacement part number 25R8079
• ServeRAID-8s SAS PCIe Controller, Option 39R8765

The system is configured with at least one of the following:

• Novell NetWare 6.5, any version
• ServeRAID Support CD, any version

Note: This does not imply that the network operating system will work under all combinations of hardware and software.

Please see the compatibility page for more information:

Additional information

The AACRAID driver is working as designed.

As Novell starts the operating system, all device drivers are loaded into a RAM space to prepare them for initialization.

After this completes, Novell imposes about a 30-second blackout period that prevents disk I/O requests going to a device that does not have a NetWare or protected mode driver loaded. Next, the device drivers start initializing. When the operating system come out from the blackout period, it is expected that the drivers have completed and registered their respective devices so that it can start doing I/O.

In this case, the AACRAID driver has not registered yet.

Because the operating system comes out of the blackout period, Novell begins doing I/O to the boot device again. Since the AACRAID driver is still not registered, it causes the device driver to switch back and forth between real and protected mode. Some short time later, Novell starts a scan to ensure all devices have registered. This scan results in a second pause the leads to the AACRAID.HAM driver loading in protected mode, registering of its devices, and starts servicing disk I/O requests.

IBM worked with both Adaptec and Novell to review the drivers behavior and in conclusion, found that this is a permanent limitation of the operating system, the controller hardware and device driver architecture and is therefore working as designed.