SAN (Storage Area Network) storage has become an essential part of IT infrastructure for organizations of all sizes. But what exactly is SAN storage and why is it so widely used? In this comprehensive guide, we’ll answer common questions about SAN storage and discuss the key benefits that make it a popular choice.
What is SAN Storage?
SAN stands for Storage Area Network. It is a dedicated high-speed network that provides access to consolidated block-level storage. SANs are primarily used to enhance storage devices accessibility for servers so that the devices appear to the operating system as locally attached drives even though they are physically located elsewhere.
Here are some key things to know about SAN storage:
- SAN storage offers consolidated storage that is shared between multiple servers.
- It provides block-level access to storage rather than file-level access.
- SANs use their own network, separate from LANs, for storage connectivity.
- Common SAN protocols include Fibre Channel, iSCSI, InfiniBand, OmniPath, NVMe over Fabrics, and more.
- SAN arrays appear to servers as locally attached drive volumes.
By providing a centralized pool of storage that can be efficiently shared between multiple servers, SANs enable organizations to consolidate their storage and get the most value from their storage assets.
Why Use SAN Storage?
There are several key advantages that make SAN storage a preferred choice for many organizations:
1. Centralized Storage
One of the biggest benefits of a SAN is centralized storage. Organizations can consolidate storage that was previously distributed in standalone storage arrays and servers into shared SAN storage arrays. This eliminates isolated storage “islands” and radically simplifies storage management.
2. Storage Consolidation
By providing shared storage infrastructure, SANs enable massive consolidation of storage resources. Rather than provisioning dedicated storage for each server, organizations can slash hardware costs by allowing servers to share common SAN storage pools.
3. Scalability
SAN storage makes it easy to scale storage capacity as needed. Additional disk drives and controllers can be added to SAN arrays to expand the available shared storage pool nondisruptively.
4. High Availability
Properly designed SANs offer greater availability versus other storage options. Features like redundant components, automated failover, and remote replication provide continuity of operations if failures occur.
5. Improved Performance
The dedicated SAN network is optimized for storage traffic, providing high bandwidth and low latency. Workloads can leverage the improved performance of SAN storage versus other options.
6. Advanced Storage Services
SAN arrays provide advanced data services including replication, snapshots, encryption, compression, auto-tiering, thin provisioning and more. These services are applied efficiently across shared storage.
7. Resource Sharing
Servers can dynamically share SAN storage resources, allowing for better resource utilization. Unused storage capacity can be easily reallocated to servers that need it.
8. Storage Networking Flexibility
SANs support flexible network connectivity using Fibre Channel SAN switch fabrics, IP-based protocols like iSCSI over Ethernet and InfiniBand. This gives organizations choices for optimizing cost and performance.
9. Ease of Management
Managing many isolated storage arrays and servers is complex and time-consuming. SANs with centralized arrays simplify the management burden with less hardware to configure and fewer points of management.
10. Investment Protection
SAN storage supports multi-vendor connectivity, protecting existing server investments. Current and new servers can access the same SAN storage pool regardless of vendor.
SAN Components
A SAN environment consists of a few key components that work together to provide consolidated shared storage:
- SAN Arrays – These are storage arrays that connect to a SAN and provide the consolidated storage pools. They contain disk drives, cache, controllers, and front-end ports.
- SAN Switches – Fibre Channel, Ethernet, Infiniband switches create a dedicated storage network connecting servers to SAN arrays. They provide interconnectivity using a high-speed switching fabric.
- Host Bus Adapters – Servers connect to the SAN through host bus adapters (HBAs) with ports matching the SAN protocol, e.g. Fibre Channel HBAs.
- Cabling – Cabling like optical fiber connects SAN components together to provide a high-speed storage network.
- SAN Management – SAN management software helps administer, monitor and troubleshoot the SAN environment.
These elements together create a dedicated storage infrastructure that enables organizations to get the most from their storage resources.
SAN vs NAS Storage
SAN is frequently compared with NAS (Network Attached Storage) which is another popular networked storage technology. There are some key differences between the two:
| SAN | NAS |
|---|---|
| Provides block-level access to storage | Provides file-level access to storage |
| SAN storage appears as locally attached drives to servers | NAS storage appears as file shares to servers |
| Leverages Fibre Channel, iSCSI, etc. as storage protocol | Leverages NFS, SMB/CIFS as file sharing protocol |
| Optimized for throughput and performance | Easier to deploy, configure and manage |
| Supports advanced storage functionality | Good for basic file sharing needs |
Generally, SAN storage is deployed for mission-critical workloads needing performance and advanced storage services while NAS provides easy file-based storage access suitable for more basic needs. Many organizations leverage both SAN and NAS storage to serve different requirements.
SAN Implementations
There are two primary architectures used when deploying SAN storage:
1. SAN Island
A SAN island consists of SAN storage arrays connected to servers via Fibre Channel. This creates an isolated pool of shared storage accessible only to connected servers. SAN islands are a simple approach to deploying SAN storage that keeps it separated from general network traffic.
2. SAN Fabric
A SAN fabric is a more advanced model that uses Fibre Channel switches to connect servers and storage arrays. This forms a flexible switched network fabric allowing any-to-any connectivity between devices. SAN fabrics enable scaling up to very large and high-performance SAN environments.
Within these architectures, there are also different SAN topologies possible including simple direct attach, switched fabric, core-edge and mesh designs. The topology can be customized to meet an organization’s specific needs.
SAN Protocols
There are several main protocols used for transporting data across a SAN network. Some common ones include:
Fibre Channel
Fibre Channel is a high-speed networking protocol designed specifically for storage networking. It provides excellent performance and reliability for connecting SAN components.
iSCSI
iSCSI allows SAN over TCP/IP networks, enabling organizations to leverage existing Ethernet infrastructures. iSCSI is popular for lower cost SAN deployments.
InfiniBand
InfiniBand offers very high throughput and low latency performance. It is commonly used for high-performance computing clusters accessing shared SAN storage.
NVMe over Fabrics
Emerging NVMe over Fabrics standards like FC-NVMe allow using NVMe storage devices over a SAN. This provides very high performance and low latency storage access.
Organizations choose SAN protocols based on their performance, cost and connectivity requirements. Many SANs use a combination like Fibre Channel for backend connections and iSCSI for front-end connectivity.
SAN Management
As a SAN scales in size and complexity, dedicated storage management tools become essential for smooth operation. SAN management software helps IT administrators perform key functions like:
- Discovering SAN devices
- Monitoring SAN health, events, capacity and performance
- Provisioning and configuring SAN storage
- Automating storage processes
- Replicating data between SAN arrays
- Optimizing data placement and cache usage
- Troubleshooting issues across SAN fabrics
Robust SAN management software centralizes control and insight into the SAN environment, enabling IT teams to efficiently manage their critical storage infrastructure.
Benefits of SAN Storage for Businesses
SAN storage offers considerable benefits that make it an attractive choice for business organizations of all sizes and across all industries:
Cost Savings
By consolidating storage onto SAN arrays, businesses can slash procurement costs for storage. SANs provide economies of scale and let you expand storage capacity easily while leveraging existing investments.
Performance
The dedicated SAN network offers much higher throughput versus general Ethernet networks. Workloads like databases, virtual machines and high-performance computing can take advantage of improved SAN performance.
High Availability
SAN storage offers uncompromising availability to keep mission-critical applications running 24/7. Features like automated failover, clustering, and remote replication deliver continuity.
Scalability
SAN fabrics make it easy to scale-up storage capacity and performance simply by adding disks, caching, and ports to arrays. Businesses can start small and grow flexibly as needs evolve.
Agility
Shared SAN storage pools with virtualization capabilities let businesses provision new resources swiftly. Rapidly deploying virtual machines and spinning up new apps helps businesses be more agile.
Disaster Recovery
SAN replication features can mirror data over distance between sites. This enables robust disaster recovery plans to restore operations quickly after outages.
Data Protection
Built-in SAN services like snapshots, cloning, encryption and access control strengthen data protection. Businesses can implement policies to guard data against loss or compromise.
Benefits of SAN Storage for Healthcare
SAN is especially advantageous for healthcare organizations due to their unique needs including regulatory compliance, data growth, reliability requirements and resource constraints. Benefits of SAN for healthcare include:
- Centralized consolidation simplifies HIPAA compliance auditing/reporting
- High scalability accommodates exponential data growth from medical images and EHRs
- High availability ensures constant uptime for electronic healthcare systems and records
- Disaster recovery enables adherence to contingency planning regulations
- Strong data protection and security help comply with privacy mandates
- Resource pooling maximizes utilization of precious IT budget and staff
With shrinking IT budgets and increasing responsibilities, SAN storage provides healthcare organizations an efficient storage foundation that cost-effectively meets regulatory requirements.
Benefits of SAN Storage for Media & Entertainment
The media and entertainment industry has demanding storage needs for video production/editing, animation, VFX rendering, and more. SAN delivers essential benefits including:
- High-bandwidth SAN delivers fast throughput for bandwidth-intensive video workflows
- Shared storage enables real-time collaboration for production teams
- Resource pooling optimizes utilization of costly animation/VFX render nodes
- Scalability handles exponential content growth from 4K, 8K and emerging formats
- Reliability and immediate restore protects irreplaceable media content
- Workload isolation guarantees uninterrupted streaming playback to consumers
For media organizations, SAN storage is indispensable for smoothly managing massive volumes of data, supporting collaboration, and ensuring fast, reliable access to their most valuable digital assets.
Benefits of SAN Storage for Financial Services
Financial services firms rely on their IT infrastructure to process millions of real-time transactions and access powerful analytics. SAN delivers vital capabilities including:
- Low latency storage IO speeds transaction processing and analytics queries
- Continuous operations prevent business disruption and revenue losses from outages
- Replication ensures disaster recovery to meet compliance mandates
- Resource sharing optimizes infrastructure for cost efficiency
- Encryption protects highly sensitive customer financial data
- Scalability to accommodate data growth from new services and acquisitions
For banking, insurance, and investment firms, SAN storage is a strategic investment that both drives and supports their business.
Benefits of SAN Storage for Education
K-12 schools and higher education have unique IT requirements that make SAN storage highly useful:
- Centralized data simplifies security, privacy and regulatory compliance
- Unified storage efficiently utilizes constrained IT budgets and resources
- High availability keeps eLearning tools and digital resources accessible
- Scalability accommodates spikes in usage and growth of digital content
- Sharing enables better use of specialized IT equipment and software
- Disaster recovery protects vital records and research data
For educational institutions, SAN storage both streamlines IT management and directly enhances teaching, research, and learning outcomes.
Benefits of SAN Storage for Government
Public sector organizations can reap many advantages from deploying SAN storage including:
- Data consolidation simplifies security, accreditation and compliance
- High availability and disaster recovery prevent disruptions in citizen services
- Centralized data facilitates open data sharing initiatives
- Scalability to support new digital services and influx of online users
- Legacy protocol support leverages existing IT investments
- Resource pooling maximizes utilization of tight IT budgets
For government agencies, SAN storage not only streamlines IT operations but also directly enables meeting public service missions.
Conclusion
SAN storage has become a foundational technology for modern IT by enabling organizations to consolidate resources, reduce costs, and leverage advanced capabilities. The benefits of performance, availability, scalability, efficiency and data services make SAN storage a go-to choice for mission-critical applications and workloads. As data demands continue growing, SAN solutions provide the enterprise-class storage organizations rely upon every day.
