Fujitsu Storage Eternus AF250 S2 review

Fujitsu makes all-Flash storage even more affordable for SMEs

IT Pro Verdict

Fujitsu’s new Eternus AF250 S2 is great choice for SMEs that want all-Flash storage, low latency and abundant data protection features at a sensible price


  • +

    Very low latency; 32Gbps FC port option; Great data protection features; All-round redundancy; Top software bundle included


  • -

    Below-par IP SAN write speeds; Auto-discover only works with FC hosts

Fujitsu has championed bringing the price of all-Flash storage down to a point where SMEs will take notice and it now goes further with its latest Eternus AF250 S2. This 2U storage array builds on the successes of its predecessor, the AF250, and aims to make all-Flash storage even more appealing.

Hardware redundancy is excellent as along with dual hot-plug PSUs, the AF250 S2 comes with dual controllers functioning in active/active mode. Data port choices have improved too, as each controller has two expansion slots which now support dual-port 32Gbps FC modules, as well as 8/16Gbps FC and 10GbE copper or SFP+ iSCSI options.

Their integral SAS expansion ports were made active in the original AF250 last year so the S2 model also allows you to double SFF drive capacity to 48 by adding a single drive shelf. The new controllers see a small speed boost with the 6-core 2GHz Xeon in the AF250 replaced with a 2.2GHz version, but maximum system cache memory stays pegged at 64GB.

Fujitsu has also made a few tweaks to its OS and its combined efforts result in a small reduction in latency and some IOPS throughput improvements. The array incorporates Fujitsu's new Cache Protection feature which replaces the capacitor in the older controllers with a long-life Ni-MH battery plus NVRAM and in the event of a blackout, the cache contents are written to memory.

Fujitsu Storage Eternus AF250 S2: IP SAN performance

Our review system came with four 10GbE SFP+ iSCSI ports and six 1.92TB HGST SS200 SSDs which we used to create a high-speed RAID10 array. For performance testing, we used a pair of Xeon E5-2600 v4 Windows Server hosts equipped with Emulex dual-port 10GbE SFP+ adapters.

With one server logged on to a 500GB target over a dual-port MPIO link, Iometer reported excellent sequential read speeds of 18.1Gbits/sec but considerably lower write rates of 9Gbits/sec which remained constant when swapping over to random operations. Dropping to 4KB block sizes saw I/O throughput for random reads and writes settle at 71,000 IOPS and 31,500 IOPS.

We logged the second server onto a dedicated target over an MPIO link and watched cumulative sequential read and write rates increase to 34.7Gbits/sec and 15.1Gbits/sec. Random operations saw a similar picture with cumulative read and write IOPS stepping up to 104,000 and 63,500.

A key feature of Fujitsu's all-Flash arrays is their low latency and the AF250 S2 didn't disappoint. For both the single server and dual server 4KB IOPS tests, we measured average read and write latencies of only 0.6ms and 1.3ms.

Fujitsu Storage Eternus AF250 S2: Installation and provisioning

Management contact is initially made via a direct connection to the first controller's remote access port. Its web console fires up a wizard which guided us through setting a hostname, securing admin access, configuring SNMP and setting the IP addresses of the controller's maintenance ports.

The main web interface hasn't seen any cosmetic changes but is easy enough to use. For storage provisioning, you start by adding selected SSDs to RAID Groups (RGs) and can choose from stripes, mirrors, RAID5 or 6 plus high-performance RAID10.

Within each RG, we created multiple volumes which were automatically assigned a LUN. For thin provisioning, you create a dedicated storage pool and as space in thin provisioned volumes (TPVs) is used, new blocks are dynamically assigned to them from this pool.

The AF250 S2 includes inline deduplication and compression which can be applied as required to TPVs. When creating a TPV, you can decide whether to have either or both of these features enabled.

Fujitsu Storage Eternus AF250 S2: Affinity Groups

Access controls are strict as Affinity Groups manage connections between hosts, ports and LUNs. First, you need to create groups for selected hosts, ports and LUNs and then link them together with Affinity Groups.

For host groups, we were disappointed to find that the array still can't auto-discover iSCSI connections so we had to enter each host's full IQN and IP address manually. From previous Eternus tests, we know that the auto-discover feature works fine with FC hosts.

The AF250 S2 scores for its integral Quality of Service (QoS) feature. This is very versatile as you can set bandwidth limits in IOPS on individual volumes, host connections and ports or choose to leave some with unlimited bandwidth.

Fujitsu Storage Eternus AF250 S2: SF Express features

All volume cloning, snapshot and replication functions are managed by the SF Express software which is installed on a separate Windows host. We loaded it on a virtualized Windows Server 2012 R2 Hyper-V VM and connected it to the array via its management port IP address.

The price we've shown includes the SF Express software, the SF Cruiser upgrade and the AdvancedCopy Manager licenses. These handle volume copy, snapshot and cloning services plus synchronous and asynchronous replication to remote Eternus appliances.

Other valuable features include advanced performance monitoring and fully automated QoS. Activating the AdvancedCopy Manager also enables copy functions for backing up targets mapped to Exchange and SQL Server hosts.

Fujitsu Storage Eternus AF250 S2: Verdict

The Eternus AF250 S2 doesn't offer any major improvements over its predecessor but it scores for its excellent data protection features and high levels of redundancy. IP SAN performance is a mixed bag but read speeds are very good while its low latency makes it ideal for performance-sensitive applications.

The price of our review system is the list price provided by Fujitsu and includes all software, the quad 10GbE iSCSI ports and the six 1.92TB SSDs which each cost around 1,800 apiece. With Fujitsu's current promotions, you can save up to 40% on the list price making the Eternus AF250 S2 an affordable all-Flash option for SMEs.


Fujitsu’s new Eternus AF250 S2 is great choice for SMEs that want all-Flash storage, low latency and abundant data protection features at a sensible price

Chassis: 2U rack

Storage: 24 SFF hot-swap drive bays

Drives included: 6 x 1.92TB HGST SS200 SSDs

Power: 2 x 805W hot-plug PSUs/fans

Dual hot-plug SAS3 controllers each with the following:

CPU: 6-core 2.2GHz Ivy Bridge Xeon

Memory: 32GB DDR3 cache/BBU

Array support: RAID0, 1, 10, 5, 6, 50, global/dedicated hot-spare

Data ports: 32Gbps FC, 8/16Gbps FC or 10GbE iSCSI (max 8)

Ports included: 2 x dual-port 10GbE SFP+ iSCSI

Expansion: External SAS3 port

Management: Web browser, SF Express

Software: Fujitsu SF Express, Cruiser Standard/QoS, AdvancedCopy Manager Local/Remote

Warranty: 3 years on-site NBD

Dave Mitchell

Dave is an IT consultant and freelance journalist specialising in hands-on reviews of computer networking products covering all market sectors from small businesses to enterprises. Founder of Binary Testing Ltd – the UK’s premier independent network testing laboratory - Dave has over 45 years of experience in the IT industry.

Dave has produced many thousands of in-depth business networking product reviews from his lab which have been reproduced globally. Writing for ITPro and its sister title, PC Pro, he covers all areas of business IT infrastructure, including servers, storage, network security, data protection, cloud, infrastructure and services.