Back to: Storage Area Network (SAN) Storage
A Storage Array is a dedicated system designed to manage large amounts of data efficiently. It consists of several hardware and software components that ensure high availability, reliability, and performance. Below is a detailed breakdown of its components, including the ones you mentioned.

1. Storage Controllers (CPU/Processor)
- Acts as the brain of the storage array, responsible for managing all storage operations.
- Typically consists of multi-core processors (Intel, AMD, or custom ASICs).
- Handles I/O processing, RAID calculations, deduplication, compression, and encryption.
- Works in active-active or active-passive configurations for redundancy.
2. Cache / RAM
- High-speed memory used to store frequently accessed data and optimize performance.
- Helps improve read/write speed by temporarily storing data before writing it to disk.
- Uses volatile (DRAM) and non-volatile (NVRAM/Flash) cache.
- Non-volatile memory ensures data persistence in case of power failure.
3. Disk Drives (HDDs/SSDs)
- The primary storage media in the array.
- Types of disks:
- HDD (Hard Disk Drive): High capacity, cost-effective, but slower.
- SSD (Solid-State Drive): Faster performance, lower latency.
- NVMe SSDs: Ultra-fast access speeds for high-performance workloads.
- Interface types:
- SATA (Slower, cost-effective)
- SAS (Faster and reliable)
- NVMe (For ultra-high performance)
4. Frontend Interfaces / Host Ports
- Connects the storage array to external servers and networks.
- Common Frontend Interfaces:
- Fibre Channel (FC): High-speed, used in SAN storage (16G, 32G FC).
- iSCSI (Internet Small Computer System Interface): Uses TCP/IP for block storage.
- NVMe over Fabrics (NVMe-oF): Low-latency, high-performance protocol.
- SAS (Serial Attached SCSI): Used in direct-attached storage (DAS).
- Supports multi-pathing for high availability.
5. Backend Interfaces / Disk Connectivity Ports
- Manages internal connections between the controllers and storage disks.
- Common Backend Interfaces:
- SAS: Used for connecting multiple disks to controllers.
- PCIe/NVMe: High-speed connectivity for NVMe SSDs.
- InfiniBand: High-performance connectivity in enterprise storage.
- Ensures high-speed data transfer between storage controllers and disk drives.
6. Ethernet Ports
- Used for management and data transfer.
- Common Ethernet speeds: 1GbE, 10GbE, 25GbE, 40GbE, 100GbE.
- Used in NAS, iSCSI SAN, and cloud storage integrations.
- Can be used for remote management, monitoring, and data replication.
7. RAID Controller
- Manages RAID (Redundant Array of Independent Disks) for data protection and performance.
- Supports RAID levels: RAID 0, 1, 5, 6, 10, etc..
- Can be hardware-based (dedicated RAID cards) or software-based.
8. Power Supplies
- Provides redundant power to prevent downtime.
- Typically configured as dual redundant power supplies.
- Supports hot-swappable power supplies for continuous operation.
9. Batteries / Backup Power
- Used for power protection to prevent data loss.
- Supports battery-backed cache (BBWC) to retain cached data during power failures.
- Can be integrated with Uninterruptible Power Supply (UPS) for extended power protection.
10. Enclosure / Chassis
- Houses disk drives, controllers, power supplies, and cooling fans.
- Modular design allows for scalability.
- Some storage arrays support disk shelves for expansion.
11. Cooling System
- Includes fans and heat sinks to prevent overheating.
- Ensures optimal performance by regulating temperature.
- High-end arrays have adaptive cooling systems.
12. Management Software & Monitoring
- Provides GUI, CLI, and API-based storage management.
- Features include storage provisioning, monitoring, alerts, analytics, and automation.
- Examples:
- Dell EMC Unisphere
- NetApp ONTAP
- HPE Storage Management Console
- IBM Storage Insights
Final Thoughts
This architecture ensures high availability, redundancy, scalability, and performance in enterprise storage environments.