IBM ServeRAID, User Reference

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2. Mixing LVD SCSI devices with single-ended SCSI devices on the same SCSI
bus will switch all devices on the channel to single-ended mode and data
rates.
v Open a case with your IBM service representative. Submit all ServeRAID logs
captured on the system for interpretation to isolate a failing component.
Locating the startup device (SCO OpenServer only)
After installing a ServeRAID controller, SCO OpenServer might fail to find the
startup (boot) device.
This problem occurs when your server locates a startup device before coming to
the ServeRAID controller on which OpenServer is installed. To solve this problem,
consult the documentation that came with your server to determine the PCI slot
scan order; then, specify the startup device.
Complete the following steps to specify the startup device:
1. Restart the server.
2. From the prompt, type the following and press Enter:
boot: defbootstr Sdsk=ips( x ,0,0,0)
where x is the number of startup devices installed before the ServeRAID
controller on which OpenServer is installed.
Solving problems in a failover environment
Use these procedures to recover from problems in a failover environment. If you still
have problems after following these procedures, contact your IBM service
representative for further information. Also, you can find hints and tips to help you
solve problems on the IBM Support Web site. See “Downloadable files from the
World Wide Web” on page 141 for additional information.
Recovering from a failure in a failover environment
In a failover environment, when the ServeRAID device driver is unable to send a
command to the active controller and the active controller does not respond to a
reset command, the device driver attempts to failover to the passive controller.
Note: Loose cables or defective physical drives will not cause a failover to occur.
Replacing a controller of a failover pair in a non-hot-plug PCI
slot
Important
Before replacing the failed controller, ensure that you have the latest device drivers, BIOS,
and firmware code installed in your server. Follow the instructions in Chapter 17, “Upgrading
a ServeRAID controller” on page 143.
If a failed controller is not in a hot-plug PCI slot, complete the following steps:
1. Shut down the server.
2. Replace the failed controller.
Note: Do not attach the SCSI cables to the new controller.
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IBM ServeRAID: User’s Reference, Version 5.10