Product manual
Table Of Contents
- VTrak Product Manual
- Contents
- Chapter 1: Introduction to VTrak
- Chapter 2: VTrak Installation
- Unpacking the VTrak
- Mounting VTrak in a Rack
- Installing Disk Drives
- Making Management and Data Connections
- Setting Up Serial Cable Connections
- Connecting the Power
- Chapter 3: VTrak Setup
- Chapter 4: Management with WebPAM PROe
- Logging into WebPAM PROe
- Choosing a Language
- Perusing the Interface
- Logging out of WebPAM PROe
- Working with the Storage Network
- Working with Subsystems
- Viewing Subsystem Information
- Saving a System Service Report
- Setting an Alias for the Subsystem
- Setting Redundancy for the Subsystem
- Setting Cache Mirroring for the Subsystem
- Setting Subsystem Date and Time
- Making NTP Settings
- Synchronizing with a NTP Server
- Viewing the Runtime Event Log
- Saving the Runtime Event Log
- Clearing the Runtime Event Log
- Viewing NVRAM Events
- Saving NVRAM Events
- Clearing NVRAM Events
- Viewing Current Background Activities
- Making Background Activity Settings
- Running Background Activities
- Running Media Patrol
- Running PDM
- Viewing Scheduled Activities
- Scheduling an Activity
- Deleting a Scheduled Activity
- Viewing Lock Status
- Setting the Lock
- Renewing the Lock
- Releasing the Lock
- Managing Users
- Managing the Network Connection
- Managing Fibre Channel Connections
- Managing SAS Connections
- Managing Storage Services
- Monitoring Performance
- Managing Software Services
- Exporting the User Database
- Exporting a Configuration Script
- Importing a User Database
- Importing a Configuration Script
- Updating the Firmware
- Viewing Flash Image Information
- Restoring Factory Defaults
- Clearing Statistics
- Saving a System Service Report
- Shutting Down the Subsystem
- Starting Up After Shutdown
- Restarting the Subsystem
- Managing Controllers
- Managing Enclosures
- Managing Physical Drives
- Managing UPS Units
- Managing Disk Arrays
- Viewing a List of Disk Arrays
- Creating a Disk Array
- Creating a Disk Array - Automatic
- Creating a Disk Array - Express
- Creating a Disk Array - Advanced
- Deleting a Disk Array
- Viewing Disk Array Information
- Making Disk Array Settings
- Creating a Logical Drive
- Deleting a Logical Drive
- Migrating a Disk Array
- Rebuilding a Disk Array
- Running Media Patrol on a Disk Array
- Running PDM on a Disk Array
- Transitioning a Disk Array
- Preparing a Disk Array for Transport
- Managing Logical Drives
- Managing Spare Drives
- Working with the Logical Drive Summary
- Chapter 5: Management with the CLU
- Initial Connection
- Running Quick Setup
- Managing the Subsystem
- Managing the Controllers
- Managing the Enclosure
- Viewing the Enclosures Summary
- Viewing Enclosure Information
- Making Enclosure Settings
- Viewing FRU VPD Information
- Viewing Power Supply Status
- Locating a Power Supply
- Viewing Cooling Unit Status
- Viewing Temperature Sensor Status
- Viewing Voltage Sensor Status
- Checking the Batteries
- Reconditioning a Battery
- Locating an Enclosure
- Viewing Enclosure Topology
- Managing Physical Drives
- Managing Disk Arrays
- Viewing a List of Disk Arrays
- Creating a Disk Array
- Creating a Disk Array - Automatic
- Creating a Disk Array - Express
- Creating a Disk Array - Advanced
- Deleting a Disk Array
- Viewing Disk Array Information
- Setting an Alias for a Disk Array
- Accepting an Incomplete Array
- Enabling Media Patrol and PDM on a Disk Array
- Preparing the Disk Array for Transport
- Rebuilding a Disk Array
- Migrating a Disk Array
- Running PDM
- Running Transition on a Disk Array
- Locating a Disk Array
- Creating a Logical Drive
- Deleting a Logical Drive
- Managing Spare Drives
- Managing Logical Drives
- Managing the Network Connection
- Managing Fibre Channel Connections
- Managing SAS Connections
- Managing Background Activity
- Working with the Event Viewer
- Working with LUN Mapping
- Managing UPS Units
- Managing Users
- Working with Software Management
- Flashing through TFTP
- Viewing Flash Image Information
- Clearing Statistics
- Restoring Factory Defaults
- Shutting Down the Subsystem
- Starting Up After Shutdown
- Restarting the Subsystem
- Making Buzzer Settings
- Chapter 6: Maintenance
- Updating the Firmware in WebPAM PROe
- Updating the Firmware in the CLU
- Downloading the Firmware Image File
- Updating the Firmware
- Restarting - Single RAID Subsystem, Telnet
- Restarting - RAID with JBOD Expansion, Telnet
- Restarting - Single RAID Subsystem, SSH
- Restarting - RAID with JBOD Expansion, SSH
- Restarting - Single RAID Subsystem, Serial
- Restarting - RAID with JBOD Expansion, Serial
- Replacing a Power Supply
- Replacing a Cooling Unit Fan or Blower
- Replacing a Cache Battery
- Replacing a RAID Controller - Dual Controllers
- Replacing a RAID Controller - Single Controller
- Chapter 7: Technology Background
- Chapter 8: Troubleshooting
- VTrak is Beeping
- LEDs Display Amber or Red
- CLU Reports a Problem
- WebPAM PROe Reports a Problem
- Event Notification Response
- Critical & Offline Disk Arrays
- Incomplete Array
- Physical Drive Problems
- Enclosure Problems
- Controller Enters Maintenance Mode
- Connection Problems
- Browser Does Not Connect to WebPAM PROe
- Unsaved Data in the Controller Cache
- Chapter 9: Support
- Appendix A: Useful Information
- Appendix B: Multipathing on Windows
- Before You Begin
- Installing PerfectPath
- Verifying Installation
- Running Perfect Path View
- Monitoring Your LUNs and Paths
- Features and Settings
- Troubleshooting
- Updating PerfectPath
- Repairing PerfectPath
- Removing PerfectPath
- Appendix C: Multipathing on Linux
- Index

Chapter 7: Technology Background
275
RAID 1 – Mirror
When a logical drive is mirrored, identical data is written to a pair of physical
drives, while reads are performed in parallel. The reads are performed using
elevator seek and load balancing techniques where the workload is distributed in
the most efficient manner. Whichever drive is not busy and is positioned closer to
the data will be accessed first.
With RAID 1, if one physical drive fails or has errors, the other mirrored physical
drive continues to function. Moreover, if a spare physical drive is present, the
spare drive will be used as the replacement drive and data will begin to be
mirrored to it from the remaining good drive.
Figure 2. RAID 1 Mirrors identical data to two drives
The logical drive’s data capacity equals the smaller physical drive. For example,
a 100 GB physical drive and a 120 GB physical drive have a combined capacity
of 100 GB in a mirrored logical drive.
If physical drives of different capacities are used, there will be unused capacity on
the larger drive.
RAID 1 logical drives on VTrak consist of two physical drives.
If you want a mirrored logical drive with more than two physical drives, see
“RAID 1E – Enhanced Mirror” on page 276 and “RAID 10 – Mirror + Stripe” on
page 279.
Data Mirror
Physical Drives