Network-attached storage, or NAS, is a type of dedicated file storage device that is connected directly to a computer network to provide centralized data access and storage to various heterogeneous clients. NAS systems contain one or more hard disk drives and a built-in network interface that allows multiple users and client devices to retrieve and store data via file sharing protocols like SMB/CIFS or NFS.
What are the key characteristics of NAS?
Some key characteristics of NAS include:
- Dedicated hardware device – NAS is its own computing system optimized for file sharing and storage.
- Network connection – Connects directly to a local area network via a standard Ethernet connection.
- Shared storage – Acts as a central repository accessible by multiple users and devices on the network.
- File-level access – Clients access data stored on the NAS at the file level via file sharing protocols.
- Scalable capacity – Additional hard drives can be added to expand storage capacity.
- Manageable – Accessed and configured via a web-based interface or vendor software.
- OS support – Supports sharing files between Windows, macOS, Linux, and other operating systems.
What are the benefits of using NAS in a network?
There are several key benefits to using dedicated NAS appliances in an organizational network:
- Centralized storage – NAS provides a single location for users to access and store files, keeping data consolidated and organized.
- Scalability – Additional hard drives can be added to NAS devices to expand their storage capacity easily as needs grow.
- Shared access – Multiple users and devices can access stored files simultaneously on the NAS over the network.
- Backups – Automated backup jobs can be configured to copy critical data from users’ PCs to the NAS for protection.
- Remote access – Users can access files stored on the NAS remotely over the internet with proper configuration.
- Improved security – Centralized NAS devices help keep sensitive files more secure instead of scattered on individual machines.
- Redundancy – RAID arrays on NAS provide fault tolerance if a drive fails.
What are the typical elements of a NAS setup?
A basic NAS configuration consists of several key hardware and software elements:
- NAS enclosure – Houses the drives, network interface, RAM, and processor.
- Hard disk drives – Provide the actual storage capacity, often arranged in RAID arrays for redundancy.
- Network interface – Ethernet port that connects the NAS to the local network.
- Processor – CPU that handles the overall management and transfer of data.
- RAM – Memory that temporarily caches frequently accessed data.
- Operating system – Specialized OS that streamlines file sharing and storage.
- Management software – Interface for configuring settings and accessing the NAS.
Many NAS units also include:
- Cooling fans to keep the drives and system from overheating.
- External I/O ports like USB 3.0 or Thunderbolt to attach additional external storage.
- Backup software for scheduled data backups to the NAS.
What protocols do NAS devices use?
NAS appliances predominantly use the following network protocols to provide seamless file access:
- SMB/CIFS – Allows Microsoft Windows and macOS users to access files stored on the NAS.
- NFS – Used by Linux and UNIX clients to connect to the NAS over the network.
- AFP – Legacy Apple Filing Protocol used for older macOS versions.
- FTP – Simple file transfer protocol can provide basic NAS access and file transfers.
- HTTP/HTTPS – Used for web-based administrative access to the NAS for management.
Many NAS systems also support integration with Active Directory and LDAP for user authentication and access permissions to the stored files.
What are the differences between NAS and traditional file servers?
There are several notable differences between dedicated NAS appliances versus traditional file servers:
| NAS | File Server |
|---|---|
| Dedicated hardware appliance optimized for storage and sharing | Runs as an application along with other services on a general purpose server |
| Streamlined operating system focused on storage and file sharing | Runs a general purpose server OS that requires more resources |
| Scales capacity by adding drives to the enclosure | Storage capacity depends on capacity of drives installed inside server |
| Data remains accessible if NAS hardware fails | Data may be inaccessible if server has issues |
| Small desktop and rackmount form factors | Designed to fit standard server racks |
In summary, dedicated NAS devices are purpose-built for optimized file storage and sharing, while file server applications provide file services alongside other server processes on general computing hardware.
What are the main uses for NAS in business networks?
There are several key business uses cases and applications for NAS technology:
- File serving – Centralized location for storing and accessing documents, spreadsheets, presentations and other departmental files.
- Backup – Primary or secondary storage target for backups of servers, PCs, laptops, and mobile devices. Also enables disaster recovery.
- Media repository – Centralized storage for multimedia files like photos, videos, and graphics libraries accessible by multiple users.
- Website hosting – Storing website files for development or internal web servers hosting intranet sites.
- Log storage – Storing logs from servers, network devices, and applications centrally for analysis and troubleshooting.
- Database hosting – Providing storage repositories for databases and database backups.
- Virtualization – Storing VM images and containers for testing and development environments.
NAS allows organizations to consolidate dispersed storage into easily managed locations that benefit various departments. IT can centrally secure and back up the data as well.
What types of RAID configurations are used in NAS devices?
NAS devices often use redundant RAID drive configurations to provide fault tolerance and protections against disk failures. Common RAID levels include:
- RAID 0 – Block-level striping without parity or mirroring. Provides performance but no redundancy.
- RAID 1 – Mirrors data across two or more disks. Provides redundancy if one disk fails.
- RAID 5 – Block-level striping with distributed parity. Provides performance and can withstand failure of one drive.
- RAID 6 – Block-level striping with double distributed parity. Similar to RAID 5 but can handle failure of two disks.
- RAID 10 – Mirrored stripped volumes, combining RAID 0 and 1. Provides performance and redundancy.
Higher-end NAS devices aimed at businesses typically use RAID 5, RAID 6, or RAID 10 to provide optimum balance of speed, capacity, and fault tolerance.
What are the benefits of using iSCSI SAN vs NAS storage?
iSCSI Storage Area Networks (SANs) and NAS have some differing strengths:
| iSCSI SAN Benefits | NAS Benefits |
|---|---|
| Block-level access provides better performance for databases | File-level access excels at unstructured data like documents and media |
| Designed for high throughput and low latency | Easier to scale out capacity by adding drives |
| Fibre Channel option provides high speed dedicated storage network | Less expensive to set up and maintain with simple Ethernet network |
| More advanced storage management capabilities | Easier for users to access and manage file storage |
In summary, iSCSI SANs excel at high performance block storage while NAS provides file-level data access optimized for collaboration and shared storage repositories.
What are the most common NAS manufacturers and models used in business?
Major enterprise NAS vendors include:
- Dell EMC Isilon
- NetApp FAS/AFF/ONTAP storage
- HPE StoreEasy
- Hitachi NAS
- IBM Spectrum Scale (GPFS)
- QNAP Enterprise ZFS NAS
- Synology RackStation
- Buffalo TeraStation
Many of these models run advanced NAS operating systems and high-performance hardware designed specifically for business use cases. Features like all-flash pools, deduplication, compression, thin provisioning, and auto-tiering deliver enterprise-grade capabilities not found in consumer NAS products.
Specific high-end business NAS models include:
- NetApp AFF A800
- Dell EMC Isilon F800
- QNAP TS-h2490FU
- Synology RS4021xs+
- HPE StoreEasy 1660
- Hitachi NAS E1040H
- IBM Elastic Storage System GL5N
These rackmount models provide large scale-out NAS storage with bandwidth reaching up to 100Gbps+ along with capacities in the multi-petabyte range in clustered configurations.
What are the key deciding factors when choosing a NAS solution for business use?
Key considerations when evaluating NAS options include:
- Storage capacity and scalability – Current and projected capacity requirements.
- Performance and bandwidth – Speed needed to support response times and throughput.
- Availability – Required uptime and redundancy features.
- Data protection – Backup, replication, and disaster recovery capabilities.
- Network connectivity – 1GbE, 10GbE, 40GbE, or Fibre Channel support.
- Protocols – SMB, NFS, iSCSI support for accessing storage.
- Management – Ease of administration and monitoring.
- Budget – Acquisition, licensing, and support costs.
Understanding current workloads and forecasting future data growth are critical to selecting the right NAS model and features.
How can you monitor and analyze performance on a NAS device?
Monitoring and analyzing NAS performance helps optimize workloads and identify potential issues. Useful metrics and methods include:
- Benchmarking baseline I/O performance to assess overall throughput.
- Tracking utilization over time to identify high activity and growth.
- Monitoring network traffic in/out of the NAS for bottlenecks.
- Checking disk I/O usage on RAID groups to find disks under high load.
- Reviewing client access patterns to optimize data locations.
- Logging SMB/NFS/iSCSI connection statistics and errors.
- Alerting on RAID events like a failed or degraded array.
- Reporting on capacity usage and growth projections.
Enterprise NAS operating systems like ONTAP or Elastic Storage System include extensive monitoring, analytics, and automated alerting capabilities. This helps optimize configurations and workload placement to maintain high availability and performance.
What are some best practices for managing and securing a NAS environment?
Recommended best practices for NAS management and security include:
- Developing a comprehensive backup plan with snapshots and replication.
- Only connecting NAS to internal networks, not directly to public internet.
- Hardening the NAS OS and disabling unnecessary services.
- Enabling access controls and permissions through integration with Active Directory or LDAP.
- Setting up automated virus scanning of files written to the NAS.
- Encrypting sensitive data at rest on the NAS via encryption modules.
- Properly physically securing NAS hardware in locked rooms or enclosures.
- Monitoring user and admin login activities for unauthorized access.
- Installing OS and firmware updates on a regular basis.
Taking a proactive and layered approach to NAS security reduces the risks of data breaches or ransomware impacting file shares.
Conclusion
Network-attached storage is an efficient, scalable technology that provides centralized file services for multiple users and systems. Key benefits like simplified data consolidation and sharing, redundancy, and remote access make NAS a versatile storage solution for enterprise IT environments. Following vendor best practices and guidelines for performance monitoring, backup, security hardening, and regular maintenance helps organizations optimize their NAS availability, integrity and productivity.