Synology’s first steps into high-availability storage was, rather surprisingly, nearly five years ago with its RC18015xs+ rack system. At the time, we felt it provided solid active/passive failover services but was expensive as it required a minimum of two diskless head units and at least one RXD1215sas expansion disk shelf.
The SA3200D aims to deliver the same protection with dual active/passive controllers but in a more affordable, self-contained system. It bears many physical similarities with Synology’s UC3200 active/active IP SAN array as it uses the same 2U 12-bay chassis and controller canisters.
The controllers are linked internally over an NTB (non-transparent bridge) hardware connection for fast cluster and heartbeat services between the active and passive controllers. All similarities with the UC3200 end there though, as the SA3200D provides all the NAS and IP SAN services Synology’s DSM software has to offer and, as with the RC18015xs+, its failover processes are non-transparent.
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SA3200D Hardware and deployment
Each controller sports a quad-core, 2.4GHz Intel Xeon D-1521 CPUs and their base 8GB of ECC DDR4 memory can be upgraded to 64GB. They have dual Gigabit and one 10GBase-T data ports while their external SAS3 ports support up to two 12-bay RXD1219sas disk shelves.
The controller’s spare PCI-E slot supports a small range of certified Synology, Intel and Marvell 10GbE or 25GbE adapter cards. For testing, we fitted our Emulex dual-port 10GBase-T cards and they were accepted without any problems.
Deployment is a swift process as you use Synology’s Web Assistant to discover the appliance and leave it to load the latest DSM software on both controllers. We installed 6TB Toshiba Enterprise SAS3 HDDs and 400GB Seagate Nytro SAS3 SSDs and used the Storage Manager to create a RAID5 array with a RAID1 SSD read/write cache assigned.
Those familiar with Synology’s DSM will experience a shallow learning curve as storage is configured and provisioned in the same manner as with its standard NAS appliances. Newcomers won’t have any problems either as the DSM interface is well-designed and very easy to use.
High availability and failover
Synology’s High Availability (SHA) app manages controller failover and provides monitoring and logging services
The Synology High Availability (SHA) app plays a key role as it provides monitoring and failover services. Along with the SA3200D, it supports most other business-class Synology appliances so you can create a high availability clusters with two identical models and use their network ports for the cluster and heartbeat connections.
A big advantage of the SA3200D is the controller connections are implemented in hardware so failover will be faster. From the SHA app, you can decide which storage services you want protected by failover, choose the ports pairs on the active and passive controllers that will be monitored and initiate a switchover on demand.
To test failover, we used an HPE ProLiant DL180 Gen10 Xeon Scalable Windows Server 2019 host. With Ping and Iometer running continuously on a NAS share mapped over 10GbE from the appliance, we initiated a controller switchover from SHA.
During the failover process, we watched our Ping lose contact with the appliance and Iometer stopped working. After 42 seconds, Ping regained contact and we could restart the Iometer test which then continued to work fine.
Clearly, the active/passive architecture will cause an interruption to services but the failover process is smooth. Furthermore, when we tested failover on the RC18015xs+, normal services were resumed in 90 seconds so the SA3200D is over twice as fast.
SA3200D 10GbE performance
You can use the SHA app to switch between controllers and failover takes less than a minute
For general 10GbE performance testing, we used the same HPE server and recorded fast Iometer sequential read and write rates for our NAS share of 9.2Gbits/sec and 8.1Gbits/sec. Real world speeds are equally good with copies of a 25GB test file returning sustained read and write rates of 5Gbits/sec and 4.6Gbits/sec.
It handled our backup test well with a 22.4GB folder containing 10,500 small files secured to the share at an average of 2.1Gbits/sec. Encryption performance is good too, as copying our 25GB file to an encrypted share returned 2.1Gbits/sec with active controller CPU utilization only reaching 22%.
It’s no slouch for IP SANs either, with a 500GB iSCSI target returning Iometer read and write rates of 9.1Gbits/sec and 8.1Gbits/sec. With a dual 10GbE MPIO link to the controller, we saw read and write rates increase to 18.1Gbits/sec and 10.4Gbits/sec.
DSM features
The ABB app provides a wealth of backup and restore features for workstations, servers and virtualized environments
With DSM at the helm, you have a wealth of storage and data protection services at your disposal. NAS share and iSCSI LUN snapshots are handled by the Snapshot Replication app while the Hyper Backup app manages local, remote, Rsync, cloud and iSCSI LUN backups.
Synology’s slick Active Backup suite offers apps for securing servers, workstations and virtualized environments plus G Suite and Office 365. Along with server and workstation protection, the Active Backup for Business (ABB) app offers agent-less backup for VMware vCentre and ESXi hypervisors and the latest version brings Hyper-V into the mix as it can protect virtual machines (VMs) created on Windows Server 2016/2019 hosts.
Synology’s Drive app provides Dropbox-like sync services for private file sharing and collaboration. Management is carried out from the separate Drive Admin Console app while users download the Drive agent or app for two-way folder syncing on Windows workstations or iOS and Android mobiles.
The Virtual Machine Manager (VMM) app allows the appliance to host VMs running any OS you choose. It offers protection plans to backup selected VMs using snapshots and it can link up with the ABB app to provide disaster recovery features for bare-metal system and VM backups.
Conclusion
The SA3200D is a vastly superior solution to the RC18015xs+ as it provides all the same high-availability services but in a single appliance and at a more affordable price. Failover between the controllers will incur service downtime but our tests show this is well under a minute and the SA3200D also provides a wealth of NAS and IP SAN storage and data protection features.
