Introduction to Next Gen Dell EMC Unity

Nearly a year later, Dell EMC has added Next Gen Unity storage systems to its existing Unity portfolio. The new models are Unity 350F, 450F, 550F and 650F. In a nutshell, This year’s Dell EMC Unity release brings in improvements to hardware as well as software i.e. improvements to UnityOE. This post examines new hardware and the new features introduced this year.

Gen2 vs Gen1

In general, the second generation Unity systems have more cores per CPU and memory when compared with the hardware introduced last year. Does that mean there must be an improvement in performance? Yes, the maximum IOPS that the new generation hardware can handle is slightly increased when compared to the older generation. Another important thing to note is that Dell EMC is going all in on All Flash and this year in the Unity product line there is no new introduction of hybrid models (spinning disks + SSD’s). The new Unity models 350F, 450F, 550F and 650F are all Flash and does not support spinning disks. Here is a table that summarizes the improvements.

Unity 350F Unity 450F Unity 550F Unity 650F
Processor Intel E5-2603v4 6-core, 1.7 GHz Intel E5-2630v4 10-core, 2.2 GHz Intel E5-2660v4 14-core, 2.0 GHz Intel E5-2680v4 14-core, 2.4 GHz
Memory 48GB (3x 16GB DIMMs) – per SP 64GB (4x 16GB DIMMs) – per SP 128GB (4x 32GB DIMMs) – per SP 256GB (4x 64GB DIMMs) – per SP
Minimum/Maximum drives 6/150 6/250 6/500 6/1000
Maximum raw capacity* 2.4 PBs 4.0 PBs 8.0 PBs 16.0 PBs **
Max IO modules 4 4 4 4
Max LUN Size 256 TB 256 TB 256 TB 256 TB
Max LUNs per array 1,000 1,500 2,000 4,000
Max File System Size 256 TB 256 TB 256 TB 256 TB

*Maximum raw capacity may vary.

**Unity 650F raw capacity is a 2x increase when compared with Unity 600F.

The look of the hardware remains the same and there is no change in the aesthetics. But on the inside, things have changed so much with the introduction of Unity OE 4.2. Before we jump on to what new in the software, Dell EMC has introduced 80 drive DAE this year. This 80 drive DAE is compatible with all generation hardware. It can work with a Gen1 hybrid, all flash arrays, and Gen2 all flash arrays.

80 Drive DAE

Photo Credit: Dell EMC

The 80 drive DAE is a dense DAE that accommodates eighty 3.5″ drives and the drives used in this DAE cannot be used in fifteen drive DAE. The new 80 drive DAE supports connecting to all generation Unity hardware. The backend connection can be x4 lanes SAS or x8 lanes SAS.

If you would like to read about Unity DPE, other DAE types and the internal components of Unity DPE check out my post Unity hardware architecture.

New features in Unity OE 4.2

Unity OE 4.2 release is a major update of this year and here is a list of most notable ones, (click the arrow to expand and read)

Dynamic Pools
Thin Clones
Enhancements to Snapshots
Improvements to system limits
Inline Compression for File
SMB migration from VNX to Unity

I will be publishing separate posts detailing the most important features of Unity OE release 4.2. Stay tuned!

Disclosure: I work for Dell EMC and this is not a promoted post.

Unity Architecture – Part I

Last year, Dell EMC announced Unity midrange storage array at EMC World. Unity is based on VNXe architecture and does not replace the higher model of VNX2, i.e. VNX8000. This post takes a closer look at Unity to understand its hardware components, design, and the software. It is a two-part series. Part I is all about Unity hardware and part II  talks about software architecture of unity.

There are three variants in Unity, Unity Hybrid, Unity All Flash and Unity VSA. The models are Unity 300/300F, 400/400F, 500/500F, 600/600F. Model with “F” at the end is all flash (only SSD’s) and the other one is a hybrid storage system (Flash + Spinning disks). Unity VSA is a virtual appliance that can be deployed on vSphere.  Now let us take a look at some of the important specifications of these models,

Specifications

The specifications listed here is for a system that runs on Unity OE 4.1 aka Falcon.

Unity 300/300F Unity 400/400F Unity 500/500F Unity 600/600F
Processor 2 x Intel 6-core, 1.6GHz 2 x Intel 8-core, 2.4GHz 2 x Intel 10-core, 2.6GHz 2 x Intel 12-core, 2.5GHz
Memory (Both SP) 48 GB 96 GB 128 GB 256 GB
Minimum/Maximum drives 5/150 5/250 5/500 5/1000
Maximum raw capacity* 2.34 PBs 3.91 PBs 7.81 PBs 9.77 PBs
Max IO modules 4 4 4 4
Max number of pools 20 30 40 100
Max LUN Size 256 TB 256 TB 256 TB 256 TB
Max File System Size 64 TB 64 TB 64 TB 64 TB
Max LUNs per array 1,000 1,500 2,000 6,000

*Maximum raw capacity may vary.

Supported disks

Unity Hybrid

SSD's
Spinning disk drives

Unity All Flash

SSD's
Solid state drives used in Unity are of eMLC and TLC type and the disks highlighted in bold are 1 WPD (write per day) disks.

Disk Processor Enclosure (DPE)

DPE holds storage processor (SP), IO modules and disks. Two variants of DPE is available,

  • 25 Drive DPE that can hold 2.5″ disks (Available for hybrid and all flash array)
  • 15 Drive DPE that can hold 3.5″ disks (Only available for hybrid array)

As seen in the table, SP in the respective model will have a different CPU model and a variable amount of memory. Both types of DPE will occupy 2U when mounted on a rack. The first four drives in Unity is DPE is called system drives. These drives contain Unity OE (Operating Environment). Remaining space in these drives can be used for storage pools. A minimum number of disks that are required to initialize system is 5. On the rear side of the DPE we have, 2x Storage Processor (1&2 on image) , 4x onboard converged network ports (Optical/Twinax) (3), 4x onboard 10 GbE Base-T RJ45 ports (4), 2x power supplies (5), IO module slots (6), 4x SAS port for backend connection (7), a management port and a service port (8). Here is the picture of DPE,

Disk processor Enclosure. Image source: emc.com

The onboard Converged Network Adapter (CNA) can be configured for 16/8/4/2 Gbps Fiber Channel SFP’s (multimode and single mode) or 10 GbE optical using SFP+ and Twinax. The other 2 on-board port on an SP is 10 GbE Base-T. All these onboard ports can be configured for Block (FC/iSCSI) or File IO (NFS/CIFS). And in each SP there is a management port (to access Unisphere) and a service port (service use or engineering use).

Each SP can have two IO modules installed to expand front end host connection. IO module installed on SPA should match what is installed on SPB respective slot. There cannot be a miss match. Following are the IO modules that Unity supports,

  • 4 port 16GB Fiber Channel
  • 10GbE Base-T
  • 1GbE Base-T
  • 2 port 10GbE Optical (SFP+ and Twinax)
  • 4 port 10GbE Optical (SFP+ and Twinax)
  • 12Gb SAS for backend expansion (Only for Unity 500 and 600)
Unity supports Active Twinax cables only and no support for Passive Twinax.

Protections space for cache (No Vault)

In the case of storage processor failure, the cache contents are dumped into M.2 SSD that resides inside each SP. If cabinet loses power, Unity SP contains an inbuilt battery backup unit (BBU) that can power the SP long enough to dump cache contents into M.2 SSD. Cache content is restored to respective SP cache when power is restored or SP is replaced. The M.2 SSD also contains Unity OE boot image.

Disk Array Enclosure (DPE)

The DAE holds drives and the number of DAE that a model supports will vary. Please refer to the specification table in the post to know the maximum DAE that a system will support. There are two variants of DAE,

  • 25 Drive DAE that can hold 2.5″ disks (2U)
  • 15 Drive DAE that can hold 3.5″ disks (3U)

On the rear side, each DAE has 4 SAS ports (marked as A & B) for DPE to DAE and DAE to DAE connection. The ports need mini-SAS HD connectors. Here are the images of 15 & 25 drive DAE,

15 drive DAE. Image source: emc.com
15 drive DAE. Image source: emc.com

That’s all about Unity hardware. In the next post, we will take a closer look at software in Unity. Stay tuned! Click here to read part II.

Disclosure: I work for Dell EMC and this is not a promoted post.