User guide
Table Of Contents
- MSA1000 User Guide
- Contents
- About this Guide
- Chapter 1: Introduction
- Chapter 2: Operating System Specific Information
- Chapter 3: MSA1000 Setup and Sample Configurations
- Chapter 4: Operation and Management
- Chapter 5: Array Configuration Utility (ACU)
- Installing the ACU on the Server
- Accessing the ACU
- Description of Screen Regions
- Configuring a New Controller
- Modifying an Existing Controller
- Probability of Logical Drive Failure
- Chapter 6: Command Line Interface (CLI)
- CLI Overview
- CLI Setup
- Help Commands
- Display Commands
- Array Controller Configuration Commands
- LUN Management Commands
- Server Connection Commands
- Selective Storage Presentation/Access Control List Commands
- Appendix A: Regulatory Compliance Notices
- Appendix B: Electrostatic Discharge
- Appendix C: Specifications
- Appendix D: Hard Drive Arrays
- Appendix E: Recovering from Hard Drive Failure
- Appendix F: Controller Display Messages
- Appendix G: Recovery ROM and ROM Cloning
- Appendix H: SCSI ID Assignments
- Index
Operation and Management
75Modular SAN Array 1000 User Guide
There are some instances in which you may replace a drive in RAID 1, RAID 5,
and Advanced Data Guarding configurations. Table 9, located in the earlier
section “Hard Drive Indicators,” illustrates the conditions when you may or may
not remove a drive in a fault-tolerant system.
Follow these guidelines when replacing drives:
■ Never remove more than one drive at a time (two drives if you are using
Advanced Data Guarding).
When you replace a drive, the controller uses data from the other drives in the
array to reconstruct data on the replacement drive. If you remove more than
one drive, a complete data set is not available to reconstruct data on the
replacement drive(s) and permanent data loss could occur.
■ Never remove a working drive.
The amber Drive Failure indicator on the drive carrier indicates a drive that
has been failed by the controller. Permanent data loss will occur if a working
drive is removed while replacing a failed drive.
■ Never remove one drive in an array while another drive in the array is
being rebuilt.
A drive’s Online indicators flash green (once per second) while it is being
rebuilt. A replaced drive is rebuilt from data stored on the other drives.
■ If the system has an online spare drive, wait for it to complete rebuilding
before replacing the failed drive.
When a drive fails, the online spare becomes active and begins rebuilding as a
replacement drive. After the online spare has completed Automatic Data
Recovery (the Online indicators will be continuously lit), replace the failed
drive with a new replacement drive. Do not replace the failed drive with the
online spare. The system will automatically rebuild the replacement drive and
reset the spare drive to an available state.
■ If you replace a drive while the system is off, it may be necessary to rebuild
the replaced drive.
■ Up to one half of the drives in a RAID 1+0 array can be replaced at the same
time.
230941-005_MSA1000_UG.book Page 75 Thursday, April 17, 2003 5:53 PM