SoftNAS Single Zone High Availability
Buurst Staff
January 28, 2021

COMING SOON – Smart HA will be available with SoftNAS 5.1


Buurst SoftNAS provides enterprise shared filesystem capabilities to cloud storage. These capabilities include data migration, control, security, performance, and for some, the most crucial feature is High Availability.

Buurst SoftNAS’ patented cross-zone SNAP HA® feature provides 5-9’s of SLA backed uptime, i.e., no more than 5 minutes of unscheduled downtime per year. While this offers excellent availability (even during a full zone failure), it also increases the cost with two independent copies of storage.

Introducing Smart HA

For customers who need more than RAID but who do not need 5-9’s of uptimewe created Dual Controller High Availability (SMART HA) solutionSMART HA provides customers a lower cost option for high availability while still providing 3-9’s of uptime (8 hours, 46 minutes of unplanned downtime per year) 

Since cloud block storage is the most expensive component in HA, the SMART HA savings can approach 50% compared to a fully replicated solution.  SMART HA does this by utilizing dual SoftNAS controller heads (2 SoftNAS instances/VMs) with a single copy of block storage, which both nodes shareThis shared block storage continues to provide high-durability (the exact number of 9’s depends on the cloud and storage type). 

Below we see the two configurations. On the left, SNAP HA operates across two availability zones, each with a redundant, replicated copy of storage. The SoftNAS controllers manage unified client access via NFS, CIFS, and iSCSI to the shared filesystems. On the right, there are still two SoftNAS controllers which share a single copy of block storage. In both cases, a single HA IP address called a Virtual IP (VIP), routes the client traffic to the current Primary SoftNAS controller. With SMART HA, the Primary controller replicates data changes to the Secondary controller, which runs in a separate zone with its copy of the block storage. 



The main difference is the two controllers share a single copy of cloud block storage, eliminating the need for replication. When a failure occurs, the Secondary controller takes over as Primary and imports the shared disk devices, effectively taking ownership of managing the shared filesystems. 

SMART HA also lets you use all the other advantages of SoftNAS, such as storage tiering, deduplication, and compression, which, when used together, can decrease the overall storage capacity by 80%. 

SMART HA is available on the marketplaces of AWS and Azure and with a BYOL license for VMware. 

softnas AWS Marketplace
SoftNAS Microsoft Azure Marketplace

Smart HA Use Cases

Cost Optimized SMART HA

Cost-optimized is for customers that require High Availability storage solution at a lower cost.  These customers are storing large amounts of. 

Typical deployment resources/components: 

  • Block storage such as SDD or HDD 
  • One copy of attached storage  
  • RAID data redundancy 
  • Lower cost compute with small amounts of RAM, CPU cores and 1Gbps network or lower 

Cost/Performance Balanced Smart HA

Cost-performance balanced is for customers who need high availability with performance. These customers are running a businesscritical and revenuegenerating workloads. 

Typical deployment resources/components: 

  • Premium SSD devices with potentially a mix of HDD
    – RAID
    – Only 1 copy of attached storage
  • Compression and deduplication
  • Tiering SSD and HDD
  • Medium cost compute likely with more RAM to be leveraged as read cache, and networks ranging from 1Gbps to 10Gbps 

Performance Optimized Smart HA 

Performance Optimized is for customers who need the highest level of performance, with a high availabilityThese customers are running highperformance use cases such as HPC, AI, and ML, where storage response is directly related to user experience. 

Typical deployment resources/component:

  • Premium and Ultra SSD or NVME devices
    – Only 1 copy of attached storage
    – RAID
  • Higher cost compute likely with lots of RAM to be leveraged as read cache, and networks ranging from 20Gbps to 100Gbps

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