QNAP ES1686DC-R2-2142IT-96G 16-Bay Dual Controller Enterprise ZFS NAS, 2.5/3.5 in. SAS 12G/6G, Xeon D-2142IT 1.9GHz CPU, 96GB RAM

QNAP ES1686dc-R2-2142IT-96G 16-Bay Dual-Controller Enterprise ZFS NAS

The QNAP ES1686dc-R2-2142IT-96G is a high-availability 16-bay Enterprise ZFS NAS with dual active-active controllers, designed for mission-critical virtualisation, database, file storage and business applications where continuous storage availability is essential. Powered by an Intel Xeon D-2142IT 8-core processor and 48GB DDR4 ECC memory in each controller, the ES1686dc R2 combines 16 hot-swappable 12Gb/s SAS drive bays, eight integrated 10GbE SFP+ interfaces, redundant power and QNAP's ZFS-based QES operating system to deliver resilient enterprise storage with advanced snapshots, SnapSync replication, inline deduplication and compression.

Dual Active-Active Controllers for High Availability

The ES1686dc R2 uses a dual active-active controller architecture, helping eliminate the storage controller as a single point of failure.

Both controllers operate within the high-availability storage architecture, supporting failover if a controller becomes unavailable.

Each controller includes its own:

• Intel Xeon D processor
• ECC system memory
• Network interfaces
• PCIe expansion
• Cache-to-Flash protection
• Management connectivity

Combined with redundant power and dual-path SAS connectivity, this architecture provides the resilience required for business-critical enterprise storage environments.

Dual Intel Xeon D-2142IT 8-Core Processors

Each controller is powered by an Intel Xeon D-2142IT 8-core/16-thread processor operating at 1.90GHz with burst speeds up to 3.0GHz.

The complete system therefore incorporates two independent enterprise-class Intel Xeon D processors.

Intel AES-NI hardware-accelerated encryption is supported, helping provide secure storage while reducing the processing overhead associated with encryption workloads.

The processing architecture makes the ES1686dc-R2-2142IT-96G well suited to:

• Enterprise virtualisation
• Database storage
• Virtual Desktop Infrastructure
• Business-critical file services
• Private cloud infrastructure
• High-performance shared storage
• Enterprise backup
• Data centre applications

96GB DDR4 ECC Memory

The ES1686dc-R2-2142IT-96G includes 96GB of DDR4 ECC system memory, with 48GB installed in each controller.

Each controller is configured with:

• 4 × 4GB RDIMM DDR4 ECC
• 4 × 8GB RDIMM DDR4 ECC
• 48GB installed memory
• 8 memory slots
• Up to 512GB supported capacity

Across the complete dual-controller system, memory can therefore be expanded to a maximum of 1TB.

ECC memory provides additional protection against memory errors, an important consideration for enterprise storage systems handling critical business data.

16 Hot-Swappable 12Gb/s SAS Drive Bays

The ES1686dc R2 provides 16 hot-swappable 3.5-inch drive bays with 12Gb/s SAS connectivity, backward compatible with 6Gb/s SAS.

Supported drive types include:

• 3.5-inch SAS hard disk drives
• 2.5-inch SAS hard disk drives
• 2.5-inch SAS solid-state drives

This provides flexibility to configure the ES1686dc R2 for high-capacity enterprise storage, high-performance SSD workloads or a combination appropriate to the required application.

Enterprise 12Gb/s SAS Storage

The ES1686dc R2 uses an enterprise 12Gb/s SAS storage architecture, providing the performance, reliability and dual-path connectivity required for demanding business applications.

Dual-path SAS connectivity complements the dual-controller architecture by helping maintain access to storage if an individual path or controller becomes unavailable.

This makes SAS particularly well suited to high-availability storage environments where continuous data access is a priority.

High-Capacity SAS HDD Storage

Support for 3.5-inch enterprise SAS hard drives allows the ES1686dc-R2 to provide substantial storage capacity within its 3U rackmount chassis.

High-capacity configurations are suitable for applications including:

• Enterprise file storage
• Backup repositories
• Data archives
• Virtual machine storage
• Shared business data
• Database storage
• Private cloud infrastructure

Organisations can select suitable enterprise SAS drives according to their required balance of capacity, performance and workload rating.

SAS SSD Support for High-Performance Workloads

The ES1686dc R2 also supports 2.5-inch SAS SSDs, allowing the system to be configured for workloads requiring high IOPS and low storage latency.

SAS SSD configurations can be particularly useful for:

• Virtual Desktop Infrastructure
• Transactional databases
• Virtual machines
• High-I/O enterprise applications
• Business-critical databases
• High-performance shared storage

This allows the same platform to address both capacity-focused and performance-focused enterprise storage requirements.

Eight Integrated 10GbE SFP+ Ports

Each controller provides four 10 Gigabit Ethernet SFP+ interfaces, giving the complete ES1686dc-R2 system a total of eight integrated 10GbE SFP+ ports.

10GbE connectivity provides substantial bandwidth for demanding storage applications including:

• Virtualisation
• iSCSI storage
• High-performance file sharing
• Database workloads
• Backup
• Replication
• Large file transfers
• Data centre storage networks

The number of integrated 10GbE interfaces also provides considerable flexibility when designing redundant storage network architectures.

Additional Gigabit Ethernet Connectivity

Each controller includes three Gigabit Ethernet RJ45 interfaces, with one assigned for remote management.

Across the complete dual-controller system this provides six Gigabit Ethernet interfaces in addition to the eight 10GbE SFP+ ports.

This allows management traffic and storage services to be separated according to the organisation's network architecture.

PCIe Expansion for Faster Networking and SAS Expansion

Each controller provides two PCIe Gen3 x8 expansion slots, giving the complete system four PCIe expansion slots.

Compatible expansion options can include:

• 10GbE network adapters
• 25GbE network adapters
• SAS expansion cards

This provides additional flexibility for organisations requiring greater network bandwidth or expanded storage capacity.

Enterprise Cache Architecture

The ES1686dc R2 incorporates an enterprise caching architecture designed to improve performance while protecting critical write data.

Caching technologies include:

• L1 ARC Read Cache: System RAM
• L2 ARC Read Cache: SSD
• ZIL Write Cache: NVRAM with Cache-to-Flash protection

This architecture helps accelerate demanding storage workloads while maintaining the data protection expected from an enterprise storage platform.

Cache-to-Flash Protection

Each controller includes a dedicated 64GB M.2 SSD for Cache-to-Flash (C2F) protection.

Cache-to-Flash technology is designed to protect cached write data during unexpected power interruptions.

This is particularly important in enterprise storage environments where uncommitted write data must be protected against sudden power or controller failures.

QES Enterprise ZFS Operating System

The ES1686dc R2 runs QNAP QES, an enterprise storage operating system based on ZFS.

ZFS provides sophisticated data integrity, snapshot and storage management capabilities designed for demanding enterprise environments.

Key capabilities include:

• ZFS architecture
• Near-limitless snapshots
• SnapSync
• Block-level data deduplication
• Inline data compression
• SMB file services
• NFS
• iSCSI

These capabilities allow the ES1686dc R2 to support both enterprise file storage and block-level storage applications.

Inline Block-Level Data Deduplication

QES supports inline block-level data deduplication, helping reduce physical storage consumption when workloads contain significant amounts of duplicate data.

Deduplication can be particularly effective for:

• Virtual Desktop Infrastructure
• Virtual machine environments
• Development and testing
• Repeated operating system images
• Enterprise backup datasets

Reducing duplicate data can substantially improve effective storage capacity in suitable workloads.

Inline Data Compression

Inline compression provides an additional method of increasing effective storage utilisation.

Compressible data can be stored using less physical capacity, allowing organisations to make more efficient use of their SAS storage infrastructure.

When combined with block-level deduplication, this can improve storage efficiency and reduce the effective cost of enterprise storage.

ZFS Snapshots for Data Protection

QES supports extensive ZFS snapshot technology, providing efficient point-in-time copies of stored data.

Snapshots can help protect against:

• Accidental deletion
• Unwanted file changes
• Data corruption
• Application errors
• Ransomware-related data modification

Point-in-time snapshots can also allow administrators to rapidly restore affected files or storage volumes without requiring a complete recovery from conventional backup media.

SnapSync Remote Replication

QNAP SnapSync provides snapshot-based remote replication between compatible Enterprise ZFS storage systems.

SnapSync can form part of an organisation's disaster recovery and business continuity strategy by maintaining replicated data at another location.

Combined with dual active-active controllers, snapshots, redundant networking and redundant power, SnapSync provides another layer of protection for critical enterprise data.

Optimised for Enterprise Virtualisation

The ES1686dc-R2-2142IT-96G is particularly well suited to enterprise virtualisation storage.

Its combination of:

• Dual active-active controllers
• Dual Intel Xeon D processors
• 96GB ECC memory
• 12Gb/s SAS storage
• Eight 10GbE SFP+ interfaces
• ZFS data protection
• Inline deduplication
• Inline compression

provides a strong platform for shared virtual machine storage.

The ES1686dc R2 supports major enterprise virtualisation platforms including VMware vSphere, Microsoft Windows Server and Citrix XenServer.

SMB, NFS and iSCSI Storage

The ES1686dc R2 supports major enterprise storage protocols including:

• SMB
• NFS
• iSCSI

This allows the system to support both file-level and block-level storage requirements.

A single ES1686dc R2 can therefore provide storage for conventional file sharing, virtualisation, databases and other enterprise applications.

Expandable Enterprise Storage Capacity

The ES1686dc R2 can be expanded using compatible QNAP SAS expansion enclosures.

This allows organisations to increase storage capacity beyond the 16 internal drive bays without replacing the primary storage platform.

SAS expansion makes the ES1686dc R2 particularly suitable for organisations expecting their enterprise storage requirements to grow over time.

Redundant Enterprise Hardware Architecture

The ES1686dc R2 has been designed to minimise single points of failure.

Enterprise resilience features include:

• Dual active-active controllers
• Redundant hot-swappable power supplies
• Dual-path SAS
• ECC memory
• Multiple network interfaces
• Hot-swappable drives
• Cache-to-Flash protection
• Battery-protected write cache

Together, these technologies create a storage architecture designed for demanding environments where service continuity is important.

3U Enterprise Rackmount Design

The ES1686dc-R2 is housed in a 3U rackmount chassis, making it suitable for enterprise server rooms and data centres.

Sixteen front-accessible hot-swappable drive bays provide convenient access for storage maintenance and drive replacement.

The rackmount design provides the redundancy, serviceability and density required for professional enterprise storage deployments.

Ideal Applications for the QNAP ES1686dc-R2-2142IT-96G

The ES1686dc-R2-2142IT-96G is particularly well suited to:

• Enterprise virtualisation
• VMware storage
• Microsoft virtualisation
• Virtual Desktop Infrastructure
• Enterprise databases
• High-availability file servers
• iSCSI storage
• Private cloud infrastructure
• High-performance shared storage
• Business-critical applications
• Data centre storage
• Enterprise backup
• Disaster recovery
• High-capacity SAS storage
• SAS SSD storage
• Organisations requiring dual-controller high availability

Technical Specifications

Specification	Details
Model	QNAP ES1686dc-R2-2142IT-96G
Product Family	ES1686dc R2
Product Type	Dual-Controller Enterprise ZFS NAS
Form Factor	3U rackmount
Controller Modules	2
Controller Architecture	Dual active-active
CPU	2 × Intel Xeon D-2142IT
CPU per Controller	8-core / 16-thread
CPU Frequency	1.90GHz, burst up to 3.0GHz
CPU Architecture	64-bit x86
Encryption Engine	AES-NI
Total Installed Memory	96GB DDR4 ECC
Memory per Controller	48GB RDIMM DDR4 ECC
Memory Configuration per Controller	4 × 4GB + 4 × 8GB
Maximum System Memory	1TB
Maximum Memory per Controller	512GB
Memory Slots	16 total / 8 per controller
Flash Memory	4GB dual-boot OS protection
Drive Bays	16 × 3.5-inch
Drive Interface	SAS 12Gb/s, backward compatible with SAS 6Gb/s
3.5-inch SAS HDD	Supported
2.5-inch SAS HDD	Supported
2.5-inch SAS SSD	Supported
Hot-Swappable Drives	Yes
SSD Cache Acceleration	Supported
L1 ARC Read Cache	RAM
L2 ARC Read Cache	SSD
ZIL Write Cache	NVRAM with C2F
Cache-to-Flash	1 × 64GB M.2 SSD per controller
10GbE	4 × 10GbE SFP+ per controller / 8 total
Gigabit Ethernet	3 × RJ45 per controller / 6 total
Remote Management	Dedicated via one Gigabit interface per controller
PCIe Expansion	2 × PCIe Gen3 x8 per controller / 4 total
Network Expansion	Compatible 10GbE/25GbE adapters
SAS Expansion	Supported
USB	2 × USB 3.2 Gen 1 per controller – engineering use
Operating System	QNAP QES
File System	ZFS
Storage Protocols	SMB, NFS and iSCSI
Inline Deduplication	Yes
Inline Compression	Yes
Snapshots	Yes
SnapSync	Yes
Power Supply	Redundant hot-swappable
Power Supply Rating	770W
Dimensions	Approx. 132 × 446.2 × 587.75mm
Net Weight	Approx. 30.22kg
Operating Temperature	0°C to 40°C
Operating Humidity	5–95% RH non-condensing

ES1686dc-R2-2142IT-96G vs ES1686dc-R2-2142IT-128G

The principal difference between the two Xeon D-2142IT models is the amount of factory-installed ECC memory.

Feature	ES1686dc-R2-2142IT-96G	ES1686dc-R2-2142IT-128G
Total Installed Memory	96GB	128GB
Memory per Controller	48GB	64GB
Memory Configuration per Controller	4 × 4GB + 4 × 8GB	4 × 16GB
Maximum Total Memory	1TB	1TB
CPU per Controller	Xeon D-2142IT 8-core	Xeon D-2142IT 8-core
Controllers	Dual active-active	Dual active-active
Drive Bays	16 × 12Gb/s SAS	16 × 12Gb/s SAS
10GbE SFP+	8 total	8 total
PCIe Slots	4 total	4 total
QES / ZFS	Yes	Yes

The 96GB version provides the same processors, storage architecture, network connectivity and high-availability capabilities as the 128GB model, but with 48GB rather than 64GB of factory-installed ECC memory in each controller.

For applications that do not initially require the additional memory of the 128GB configuration, the ES1686dc-R2-2142IT-96G provides the same core enterprise storage architecture while retaining expansion capability up to 512GB per controller.

Why Choose the QNAP ES1686dc-R2-2142IT-96G?

The QNAP ES1686dc-R2-2142IT-96G combines enterprise-class high availability, powerful Intel Xeon processing and advanced ZFS data protection in a flexible 16-bay SAS storage platform.

Dual active-active controllers help maintain storage availability during controller failures, while each controller includes an 8-core Intel Xeon D-2142IT processor and 48GB DDR4 ECC memory, providing 96GB total factory-installed memory.

Sixteen 12Gb/s SAS bays support high-capacity enterprise SAS hard drives and high-performance SAS SSDs, while eight integrated 10GbE SFP+ interfaces provide substantial bandwidth for virtualisation, databases and other demanding shared-storage applications.

QES adds ZFS snapshots, SnapSync replication, inline block-level deduplication and compression, while NVRAM and Cache-to-Flash technology help protect critical write data.

For organisations requiring high-availability Enterprise ZFS storage, dual-controller redundancy, 12Gb/s SAS, 10GbE networking and powerful Xeon processing, the QNAP ES1686dc-R2-2142IT-96G provides a scalable platform for mission-critical storage infrastructure.