NAS (Network Attached Storage): A device primarily designed to store and share files over a network.
SAN (Storage Area Network): A network of storage devices that provides consolidated storage solutions for multiple servers.
Historical Context
Early Days (2002 and prior): Data was stored on servers (Windows 2000, 2003, UNIX).
Emergence of dedicated storage devices that focus solely on data storage rather than other tasks like Active Directory or virtualization.
NAS Overview
Purpose: Acts as a file server.
Functionality:
Only serves files and doesn’t run additional applications.
Data storage capacity can range from a few terabytes to several petabytes.
Protocols Used:
Standard file transfer methods: FTP, SMB, CFS, Apple File Protocol.
Security: More secure than general-purpose servers since they are dedicated only to file storage.
Examples of NAS Software:
FreeNAS: A free operating system for creating NAS devices.
Benefits of NAS
Simplicity: Designed specifically for file storage, reducing risk from user activities (e.g., internet browsing, software installs).
Increased Security: Less prone to misuse compared to general servers.
SAN Overview
Purpose: A collective network of storage devices that deliver multiple storage solutions.
Functionality:
Creates clusters of storage devices; if one fails, data remains accessible via the network.
Allows mapping of drives such that SAN folders function like local drives.
Data Redundancy: If a SAN device fails, another in the cluster keeps the data accessible.
Advantages of SAN
Flexibility in Storage: Adding new storage (e.g., a 10TB box) can be done easily without user downtime.
Seamless Scaling: Expanding storage within SAN is simpler than traditional server upgrade processes.
Virtualized Environments:
SAN supports virtualization, allowing instances to be stored centrally and run on any server in the network.
Virtualization and SAN
Backing Up Virtual Instances: Instances run on hypervisors can be migrated between physical servers depending on resource availability.
Storage Location: Instances are stored on the SAN, retrieved by hypervisors as necessary.
Storage Networking Technologies
Fibre Channel:
High-speed networking solution (2 to 16 Gbps) primarily used in enterprise SANs.
Connects SAN devices and servers for fast data transfers.
iSCSI: A cost-effective alternative for basic SAN setups, transferring data over standard Ethernet connections.
Cost and Implementation
Fibre Channel Price Range: High-cost equipment (potential costs of $250,000+ for a SAN solution with multiple devices).
Home Labs: iSCSI provides a more accessible method for experimenting with SAN technologies at a lower cost.
Conclusion
Understanding NAS and SAN is crucial for modern data management solutions, enabling better performance, security, and redundancy.
This shifts the perspective from monolithic servers to a modular infrastructure, ensuring continuous availability and scalability in storage solutions.