Let's find how what a modern dual-controller IP SAN looks like, Synology-style

Sponsored The term “mission critical” has been widely applied to different IT systems over the decades but never has it been so apt as now, with IT workloads running “always on” businesses that are founded on virtual, hybrid infrastructures.

These workloads are expected to run smoothly yet the data these services rely upon straddles a range of systems running on-premises, with Managed Service Providers and other hosted services. The diverse and distributed nature of this infrastructure means performance and uptime challenges for the storage tiers on which the corporate data resides.

Adding further complication is the fact that everything - it seems - must be given equal priority when it comes to resilience and back up: all data must be stored, all data protected and all replicated. Oh, and in the event of disaster, it must be easily recoverable, too.

Increased expectations

The objectives are pretty simple, however any IT team speccing out or buying a storage and back-up layer knows that the devil is in the details - that the effectiveness of the final system they deploy could be hampered by a number of factors. Certain key considerations must therefore be entertained before committing to a new stack. Among those considerations: what will impact the time to recovery of a service? Will setup and management be straight-forward? Will your system be cross-platform and can you expect support from the manufacturer during the crucial setup phase?

With these considerations in mind, Synology has stepped in with the Unified Controller UC3200 iSCSI Server. Built for mission-critical environments, the UC3200 iSCSI Server is Synology’s first enterprise storage IP SAN model with active-active dual controllers. As a software developer and hardware manufacturer, Synology has taken a holistic approach - unlike some. It’s developed a dual-controller IP SAN system that tightly integrates the software and hardware so as to enhance performance, improve reliability and help speed up recovery.

Performance and protection

Synology’s debut system is all about performance. The active-active design gives each controller its own Intel Xeon D-1521 4-core processor and memory (8 GB DDR4 ECC UDIMM, expandable up to 64 GB). Each has its own network controller, ports and PCIe slots ensuring the critical iSCSI services are highly available, maximizing system uptime for applications. In terms of performance, the UC3200 delivers more than 400,000 random read IOPS and 143,000 random write IOPS. A single unit holds 12 3.5”/2.5” SAS drives of up to a huge 192TB of capacity and with expansion units it can scale to 576TB.

Inter-connectivity with the UC3200 comes through the high-speed Non Transparent Bridge (NTB) between each controller. This lets one controller take over the service seamlessly if the other breaks down. In addition, the UC3200 syncs all cached data between the controllers, avoiding data loss in case of controller failure before data is written into the hard disks. The use of the NTB on the dual controllers is the difference between a high-quality dual controller and others out there that are marketed as offering the same level of performance and reliability.

Operating-system stability

The UC3200 injects a new level of stability into the concept of an array. A traditional array set up with 12 drives will have the operating system written on those hard drives. While this is not in itself a problem, it does have a huge impact on the system should there be a hard drive failure that leads to an array rebuild.

Synology’s DiskStation Manager operating system, which is based on Linux and renowned for its stability. With a SATA-DOM, memory is allocated for all the services to operate separately from the storage. The built-in SATA-DOM on each controller is used only for running the operating system, thereby separating system partition and data to help improve the system’s stability.

The operating system is pre-installed on the UC3200, meaning out-of-the-box set-up is simple and fast - thereby helping you to save time and resources from the start. Nor do you need to track down third-party software or check compatibility with the server, as can happen with other systems, a fact that helps remove the standard overhead to deliver more optimal performance.

Modified and optimised Linux inside

What exactly is running inside the UC3200? Synology has employed the Btrfs file system that’s used in Linux and is based on the copy-on-write principle, which brings additional deduplication to copy-on-write snapshots. Btrfs was built to address and manage large storage subsystems and it supports advanced fault tolerance, online defragmentation and resource pooling among other features. It has been used at large scale by, among, others Facebook who employed Btrfs in traffic optimisation.

Synology’s Btrfs implementation is not a simple copy-on-write but - rather - redirect-on-write, something that brings many benefits in a dual-controller implementation. It reduces the number of operations and the impact on performance. The Btrfs modules implemented by Synology in the UC3200 cover data protection – notably for snapshotting. You get two copies of metadata under this system, thereby making it possible to determine whether data has been corrupted.

In terms of that all-important networking, the UC3200 comes 25GbE ready. It features a single 10GbE and dual 1GbE RJ-45 ports per controller and supports 10GbE / 25GbE network interface card expansion with PCIe 3.0, boosting network bandwidth with Link Aggregation.

Failover in a virtualized world

Virtual Machines are becoming ubiquitous and when it comes to failover and recovery, they present their own challenges. The fact VMs are no longer the preserve of test environments or short-term workloads makes these challenges a concern in operations. To help sidestep these, the UC3200 has been built to be virtualisation-ready by virtue of the fact it can integrate easily with such platforms as VMware vSphere, Citrix XenServer and OpenStack Cinder.

As for failover, the UC3200 has been built to be non-disruptive – vital for the stability of VM environments and a feature made possible by the active-active dual controller. With both controllers operating at any given time, failover time is drastically reduced compared to an active-passive model.

Management and support

Outside of these detailed internals, we have management and support. The UC3200 comes with an intuitive management dashboard interface based on Synology’s award-winning DSM streamlined for iSCSI and data protection, making this a storage system that’s simple to get to grips with. In addition Synology works with specialist international partners who are expert in everything from set up to configuration and management and provide 24/7 support. The UC3200 also comes with a five-year manufacturer’s warranty.

Simple and elegant

Data growth is not slowing down and the use of multiple clouds is becoming standard practice, so much so that multi-cloud management has been forecast as a huge growth market. More than 75 per cent of enterprise IT leaders expect to be using multiple clouds by 2020. It’s seen as the answer to multiple challenges including data storage and transport, availability, recovery and location, and the growth in non-traditional enterprise workloads such as AI.

In this increasingly complex world, IT pros need all the simplicity they can get. With the UC3200, Synology has created a fully integrated storage package based on the active-active dual controller model that will mean easier deployment, configuration, operation and on-going management. All that, plus enterprise-class features in scale, performance, reliability and recovery.

Sponsored by Synology.