Dell EMC SC5020 Storage Array

It’s hard to believe the popular SC4020 has been around for over 3 years now and recently Dell EMC have announced its successor, the SC5020. This post will look at some of the key differences and improvements to the mid-range SC storage array.


The first thing to note is the SC5020 has a new 3U form factor which is similar to its bigger brother, the SC7020. Mounting the drives horizontally has allowed the drive count to increase to 30 x 2.5” drives before expansion enclosures are required.

The controllers have also been given a refresh with each one containing an eight core Intel Xeon processor and 64GB RAM (a four fold increase over the SC4020).  The array supports a 12Gb SAS backplane (6Gb on the SC4020) and now supports the SC400 and SC420 12Gb SAS expansion enclosures. Dell EMC plan to release an ultra-dense storage option this summer which I’m guessing will be called the SC480. It’s possible to support up to 2PB of capacity over 222 drives on a single array with the option to federate if you need more capacity than this.

One annoyance I did have with the SC4020 was it only supported 10Gb iSCSI using SFP+. Now this isn’t usually a big deal if you have budget to replace the storage switches but many customers are choosing to migrate away from the PS (EqualLogic) range using a staged approach or have limited budget meaning 10Gb switches are not an option. Dell EMC did release a firmware upgrade with SCOS 6.6 to allow management and replication ports to be used with iSCSI but this sometimes meant additional networking configuration was required to support this.


With the SC5020 we have some good news – you now have an option to choose either Base-T or SFP+ for the mezzanine cards for 10Gb iSCSI. In addition there is also a PCIe slot available on each controller with options for SAS, iSCSI Base-T, iSCSI SFP+ and Fibre Channel cards to support multi-protocol arrays.


The array is released with SCOS 7.2.1 and supports all the common SCOS 7.x features including

  • Dynamic RAID tiering
  • Data Progression auto-tiering
  • Hybrid and all flash options
  • Intelligent deduplication and compression
  • Live Migrate multi-array federation (with volume advisor)
  • Live Volume with auto failover
  • QoS, VVols and VLAN tagging
  • Thin clones, snapshots, replication
  • SED support
  • Dell Storage Manager (DSM)
  • PS series coexistence (full replication with legacy PS arrays)


Dell EMC have simplified the licensing with the SC5020. With the SC4020 you purchased a base license which covered up to 48 active drives. Anything above this expansion packs were required and purchased in 24 drive increments - so adding that 49th drive could have been difficult to budget for. Now all SC5020 licenses are unlimited up to the full drive capacity of the array. This applies to both the base license and the advanced features license packs making licensing much simpler than the SC4020.

If you are not familiar with the SC licensing options the Core OS or base license provides the following features

  • Snapshots
  • Dynamic Capacity (thin provisioning)
  • Live Migrate
  • Dell Storage Manager (DSM)
  • Deduplication and Compression
  • Dynamic Controllers and Virtual Ports


There are also two optional feature bundles available at an additional cost. The Storage Optimisation bundle unlocks Data Progression (tiering) and Fast Track (only applicable to HDD) features whilst the Storage Protection bundle provides Live Volume, Remote Instant Replay (replication) and Replay Manager features. If you want something a bit more bespoke then individual feature licenses are available.


As with all other SC arrays management and administration is done using the Dell Storage Manager (DSM) tool. DSM also supports the management of PS arrays to giving you that single point of management during in a migration or phased replacement. For those of you running vCenter the Dell Storage Integration Tools for VMware or DSITV for short can be deployed allowing you to configure, monitor, manage and protect workloads running on SC platform using the vSphere Web Client.


With the acquisition of EMC last year Dell EMC are now making the SC arrays interoperable with tools and solutions traditionally only available to EMC customers. This includes software such as Dell EMC PowerPath, ViPR suite and Cloud Array technology along with data protection software such as Dell EMC Data Domain and Recover point. Full details can be found by clicking the link below.


The table below shows the key differences between the SC4020 and the SC5020 arrays.

Untitled Document
  SC4020 SC5020

Rack Units



Internal Bays

24 2.5" 30 x 2.5"
Max Drives Supported 192 222
RAM 16GB per controller 64GB per controller
CPU 2.5GHz 4C per controller 2.4GHz 8C per controller
Max RAW Capacity 1PB 2PB
SAS Backend 6Gb SAS 12Gb SAS
Networking 10Gb SFP+, 1Gb Base-T 10Gb SFP+, 10GB Base-T, 1Gb Base-T
PCLe Support No 1 x slot
Licensing Per 48 drives with 24 drive expansion pack Unlimited drive licensing

Max Snapshots

4096 8192
Max Source Replications 256 500
Max Target Replications 1024


Whilst there is a shift towards software defined or hyper-converged solutions the traditional storage array is still very relevant and with five different models to choose from the Dell EMC SC range is a good fit for most workloads. For those of you who have different refresh cycles with servers and storage it’s sometimes difficult to make the transition to a HCI based infrastructure when it comes to budget. If you are considering replacing your storage platform or have a new requirement the SC range is certainly worth considering. Thanks to the updated hardware specification on the SC5020 we can now expect to see more IOPS, throughput and overall capacity than the SC4020 whilst still offering all the expected enterprise grade features at an affordable cost. If you would like to know more about the SC range please do get in touch.