A P P E N D I X B - Firmware Specifications

A P P E N D I X B

Firmware Specifications

This appendix contains the firmware specifications in the following tables:

Basic RAID Management

Advanced Features

Caching Operation

RAID Expansion

Redundant Controller

Data Safety

Security

Environment Management

User Interface

TABLE B-1 Basic RAID Management
Feature	Description
RAID Levels	0, 1, 1+0, 3, 5, 10, 30, and 50. Enhanced RAID levels supported (with logical volume implementation).
Maximum Number of Logical Drives	32
Raid Level Dependency to Each Logical Drive	Independent. Logical drive configured in different RAID levels can coexist in an array.
Logical Drive Identification	Unique, controller-generated logical drive ID; logical drive name is user-configurable.
Maximum Number of LUNs per Host ID	Up to 32, user-configurable.
Concurrent I/O	Supported.
Tag Command Queuing	Supported.
Dedicated Spare Drive	Supported; defined as the spare drive specifically assigned to a logical drive.
Global Spare Drive	Supported; the spare drive is available for all logical drives.
Auto-Rebuild Onto Spare Drive	Supported.
Auto-Scan of Replacement Drive Upon Manually Initiated Rebuild	Supported.
One-Step Rebuild Onto Replacement Drive	Supported.
Auto-Rebuild Onto Failed Drive Replacement	Supported. With no spare drive assigned, the controller auto-scans the failed drive and starts to rebuild automatically once the failed drive has been replaced.
Auto Recovery From Logical Drive Failure	Supported. When a user accidentally removes the wrong drive to cause the second drive failure of a one-drive-failed RAID 5 or RAID 3 logical drive, switches off the controller, puts the drive back, and powers on the controller. The logical drive is restored to one-drive-failed status.

TABLE B-2 Advanced Features
Feature	Description
Drive Low-Level Format	Supported.
Drive Identification	Supported. Forces the drive to light the activity indicator so the user can recognize the correct drive.
Drive Information Listing	Supported.
Drive Read/Write Testing	Supported.
Configuration on Disk	Supported. The logical drive information is recorded on drive media.
Save and Restore NVRAM to and From Disks	Supported. Saves all the settings stored in the controller NVRAM to the logical drive members.
User-Configurable Geometry Range	Sector: 32, 64, 127, 255, or Variable. Head: 64, 127, 255, or Variable. Cylinder: <1024, <32784, <65536, or Variable.
Drive Motor Spin-Up	Supported. The controller sends spin-up (start unit) command to each drive at four-second intervals.
Drive-Side Tag Command Queue	Supported. User-adjustable up to 128 for each drive.
Host-Side Maximum Queued I/O Count	User-adjustable up to 1024.
Maximum Concurrent Host- LUN Connection	User-adjustable up to 64.
Number of Tags Reserved for Each Host-LUN connection	User-adjustable up to 256.
Drive I/O Timeout	User-adjustable.

TABLE B-3 Caching Operation
Feature	Description
Write-Back and Write-Through Cache	Supported.
Supported Memory Type	SDRAM memory for enhanced performance. Fast Page Memory with Parity for enhanced data security.
Scatter / Gather	Supported.
I/O Sorting	Supported. Optimized I/O sorting for enhanced performance.
Variable Stripe Size	RAID 0, RAID 1, RAID 5: Optimization for random I/O (32 Kbyte), optimization for sequential I/O (128 Kbyte), user selectable. RAID 3: Optimization for random I/O (4 Kbyte), optimization for sequential I/O (16 Kbyte), user selectable.

TABLE B-4 RAID Expansion
Feature	Description
On-Line RAID Expansion	Supported.
RAID Expansion - Add Drive	Supported. Multiple drives can be added concurrently.
RAID Expansion - Copy and Replace Drives	Supported. Replace members with drives of larger capacity.

TABLE B-5 Redundant Controller
Feature	Description
Active-Active Redundant Controller	Supported.
Synchronized Cache for Both Controllers	Supported.
Write-back Cache Enabled in Redundant Controller Mode	Yes; with synchronized cache connection between controllers.
Hot-Swappable Controller	Supported.
No Single-Point-of-Failure	Supported.
Dynamic Cache Memory Allocation	Yes. Cache memory is dynamically allocated, not fixed.
Cache Battery Backup	Supported.
Load-Sharing	Supported. Workload can be flexibly divided between different controllers by assigning logical drives to different controllers.
User-Configurable Channel Mode	Supported. Channel modes are configurable as HOST or DRIVE in both single-controller and redundant controller mode.
Redundant Controller Rolling Firmware Upgrade	Firmware upgrade can be downloaded to the primary controller and then be adopted by both controllers.
Redundant Controller Firmware Synchronization	In the event of controller failure, a replacement controller running a different version of firmware can restore a redundant array with a failed controller. Different firmware versions can be autosynchronized later.

TABLE B-6 Data Safety
Feature	Description
Regenerate Parity of Logical Drives	Supported. Can be performed periodically by the user to ensure that bad sectors do not cause data loss in the event of drive failure.
Bad Block Auto-Reassignment	Supported. Automatic reassignment of bad blocks.
Battery Backup for Cache Memory	Supported. The battery backup solutions provide long-lasting battery support to the cache memory when power failure occurs. The unwritten data in the cache memory can be committed to drive media when power is restored.
Verification on Normal Writes	Supported. Performs read-after-write during normal write processes to ensure data is properly written to drives.
Verification on Rebuild Writes	Supported. Performs read-after-write during rebuild write to ensure data is properly written to drives.
Verification on LD Initialization Writes	Supported. Performs read-after-write during logical drive initialization to ensure data is properly written to drives.
Drive SMART Support	Supported. Default: Detect and Clone+Replace
Clone Failing Drive	Users can choose to clone data from a failing drive to a backup drive manually.

TABLE B-7 Security
Feature	Description
Password Protection	Supported.
User-Configurable Password Validation Timeout	Supported. After a specific period of time without any user interaction, the password is requested again. This prevents unauthorized operation when the user is away.

TABLE B-8 Environment Management
Feature	Description
SAF-TE and SES Support	Supported.
SAF-TE and SES Polling Period	User-configurable (50 ms, 100 ms, 200 ms, 500 ms, 1~60 sec).
SAF-TE and SES Temperature Value Display	Supported. Displays the temperature value provided by enclosure SAF-TE module (if available).
On-Board Controller Voltage Monitors	Supported. Monitors the 3.3V, 5V, and 12V voltage status. Event trigger threshold user-configurable.
On-Board Controller Temperature Sensors	Supported. Monitors the CPU and board temperature status. Event trigger threshold user-configurable.
Enclosure Monitoring of Redundant Power Supply Status, Fan Status, UPS Status, and Temperature Status	Supported. Fault-Bus, SAF-TE, SES, ISEMS.

TABLE B-9 User Interface
Feature	Description
RS-232C Terminal	Supports terminal modes: ANSI, VT-100, ANSI Color. Provides menu-driven, user-friendly, text-based interface.
Ethernet Interface	Supports 10BASE-T communication for out-of-band management.
Beeper Alarm	Warns user when any failure or critical event occurs.

Copyright © 2009, Dot Hill Systems Corporation. All rights reserved.