EMC Symmetrix DMX-3

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EMC Symmetrix DMX-3 Product Guide
Data Integrity, Availability, and Protection
Overview
The Symmetrix system has many features and options to ensure a
high degree of system and data availability. Many of these features
and options are built into the Symmetrix design. Other availability
options may be purchased separately and implemented into the
Symmetrix system operation.
Symmetrix reliability
and availability
features
The Symmetrix system design offers the following reliability and
availability features:
◆ High-reliability components
◆ Global memory director redundancy
◆ Redundant global memory
◆ Channel director redundancy
◆ Redundant internal data paths
◆ Internal control data path redundancy
◆ Fibre Channel back-end redundancy
◆ Dual-Initiator feature
◆ Redundant power subsystem
◆ Vaulting
◆ System battery backup
◆ Nondisruptive maintenance and microcode upgrades and loads
These basic Symmetrix features provide protection against loss of
system and data availability due to a power loss or failed component.
A redundant design allows the Symmetrix system to remain online
and operational during component repair. For example, if a power
supply fails, the remaining power supplies share the load until the
failed component is replaced. The system battery backup prevents
any loss of data due to a power failure.
Symmetrix data
integrity protection
features
The Symmetrix system is designed with these data integrity features:
◆ Error checking, correction, and data integrity protection
◆ Disk error correction and error verification
◆ Global memory error correction and error verification
◆ Periodic system checks
Error verification prevents temporary errors from accumulating and
resulting in permanent data loss. Symmetrix systems also evaluate
the error verification frequency as a signal of a potentially failing
component.