Back to: Storage Area Network (SAN) Storage
Switched Fabric (FC-SW) SAN Topology
Switched Fabric (FC-SW) is one of the primary Fibre Channel (FC) SAN topologies that provides a highly scalable and resilient storage network. It utilizes Fibre Channel switches to interconnect devices, allowing multiple paths, high availability, and efficient traffic management.
1. Overview of Switched Fabric SAN
Switched Fabric (FC-SW) SAN topology is based on dedicated Fibre Channel switches that route data between storage devices and servers (hosts). Unlike direct-attached storage (DAS) or arbitrated loop (FC-AL), FC-SW offers high-speed connectivity, dynamic path selection, and redundancy.
Key Features of FC-SW SAN:
- Scalability – Supports thousands of devices.
- High Availability – Multiple redundant paths prevent single points of failure.
- Performance – Dedicated bandwidth between nodes.
- Zoning & Security – Allows logical segmentation of devices.
- Multipathing – Enables load balancing and failover mechanisms.
2. Components of an FC-SW SAN
a. Fibre Channel Switches
- Director-Class Switches – High-port density (up to thousands of ports), enterprise-grade redundancy.
- Fabric Switches – Mid-range switches, used in medium to large environments.
b. Storage Arrays
- FC-enabled storage arrays connect to the fabric to provide shared storage access.
c. Host Bus Adapters (HBA)
- FC HBAs in servers allow them to connect to the SAN fabric.
d. Fibre Channel Cables & SFPs
- Optical fiber (Single-mode, Multi-mode) or copper cables.
3. Switched Fabric (FC-SW) Architecture
a. Single-Switch Fabric
- A single Fibre Channel switch connecting multiple servers and storage devices.
- Suitable for small environments but lacks redundancy.
b. Multi-Switch Fabric
- Multiple switches interconnected to form a larger fabric.
- Provides redundancy and load balancing.
c. Core-Edge Topology
- Core Switches: High-performance switches for inter-switch communication.
- Edge Switches: Connects to hosts and storage.
- Used in enterprise environments for scalability and performance.
4. Zoning in Switched Fabric
Zoning controls which devices can communicate in the SAN, enhancing security and performance.
Types of Zoning:
- Soft Zoning: Based on WWN (World Wide Name). Flexible but less secure.
- Hard Zoning: Based on switch ports. More secure and enforced at hardware level.
5. Multipathing and Load Balancing
- FC-SW SANs support multipathing for redundancy and performance optimization.
- Multipathing software (e.g., MPIO, PowerPath) enables multiple active paths.
6. Advantages of Switched Fabric SAN
✅ High Speed (16G, 32G, 64G Fibre Channel)
✅ Redundant Paths for High Availability
✅ Supports Large Scale Deployments
✅ Advanced Traffic Management & QoS
✅ Secure and Reliable Data Transfers
7. Use Cases
✔ Enterprise Data Centers
✔ High-Performance Computing (HPC)
✔ Mission-Critical Applications
✔ Virtualized Environments
Conclusion
Switched Fabric (FC-SW) SAN topology provides a robust and scalable storage networking solution for enterprise environments. It ensures high availability, security, and efficient data traffic management, making it ideal for large-scale IT infrastructures.