IBM Netfinity ServeRAID-4H Ultra160, User Reference

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Chapter 3. Configuring two ServeRAID controllers in a failover
environment (Windows NT 4.0 and Windows 2000 only)
You can configure two ServeRAID controllers in a failover environment when using
Windows NT 4.0 or Windows 2000. The latest version of the ServeRAID device
drivers includes fault tolerant technology. With fault tolerance, you can pair two
controllers and connect them to the same enclosure in order to provide access to
the disk, even after a controller fails.
Hardware requirements
Important
To perform fault tolerance, you must use only matched pairs of controllers. The controllers
must be identical, including the level of BIOS and firmware on the controllers.
You can use the following pairs for fault tolerance:
v
Two ServeRAID-4H
v
Two ServeRAID-3HB
v
Two ServeRAID-3H
v
Two ServeRAID-3L
v
Two ServeRAID-II
Note: If your system has a ServeRAID controller built-in on the system board, you
cannot use the built-in controller in the fault-tolerant pair.
In order to perform fault tolerance with ServeRAID controllers, you must use one of
the following enclosures:
v
IBM PC Server Enterprise Expansion Enclosure (3518), using IBM SCSI-2
Fast/Wide Enhanced Repeater Adapter
v
IBM Netfinity Rack Drawer Enclosure (3519), using IBM SCSI-2 Fast/ Wide
Enhanced Repeater Adapter
v
IBM Netfinity EXP10 Rack Storage Enclosure, using Netfinity EXP10 3m External
Auto-Sensing Cable
v
IBM Netfinity EXP15 Rack Enclosure
v
IBM Netfinity EXP200 Rack Enclosure.
Installation guidelines and restrictions
Important
If any of the following restrictions and guidelines are not met, failover is disabled for the
controller pair and an error explaining the problem is logged in the system event log. To
verify that the configuration is OK, start the ServeRAID Manager program on the Windows
NT or Windows 2000 server. The Main Tree of the ServeRAID Manager displays controller
pairs that are configured for failover correctly.
In order to perform fault tolerance with ServeRAID, you must adhere to the
following guidelines and restrictions.
v
The stripe-unit size and firmware level must be the same on both controllers.
v
A fault-tolerant pair cannot be part of a Microsoft Cluster Service shared cluster.
v
All logical drives on the controller must be configured as write through.
© Copyright IBM Corp. 2000
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