This consists of a collections of questions asked that we felt would be of interest by others looking at Buurst and SoftNAS. If you don't see a subject you are interested in, or have a specific questions wanting answered, don't hesitate to contact us.

General Questions

Buurst is a trusted provider of high performance cloud applications, notably a Cloud NAS, object storage filer, and cloud data management software called SoftNAS, which allows companies to migrate their data and applications into the cloud without re-engineering.  Founded in 2012 as a cloud-first software company, Buurst (formerly SoftNAS)holds several patents, including patents for cross-zone high-availability and failover and for a congestion avoidance algorithm that accelerates writes to object storage. Fortune 500 to SMB companies across multiple industry verticals trust SoftNAS with their mission-critical data. Buurst provides a frictionless customer experience and is the only cloud software storage company to offer a No Storage Downtime Guarantee™.

NAS is a common IT term for Network Attached Storage that enables data and file sharing using popular protocols like NFS and CIFS/SMB. iSCSI is typically associated with SAN (Storage Area Networks). NAS storage systems that support NFS, CIFS/SMB, and iSCSI are termed “unified” storage. SoftNAS provides unified storage designed and optimized for high-performance, higher than normal I/O per second (IOPS) and data reliability and recoverability. It also increases storage efficiency through thin-provisioning, compression and deduplication.

SoftNAS is a hybrid cloud data integration product, combining a software-defined, enterprise-class NAS virtual storage appliance, backups and data movement; and data integration/replication for IT to manage and control data centrally. Customers save time and money while increasing efficiency. 

SoftNAS supports Cloud deployment on AWS and Azure, and on-premise deployment via VMware. 

General SoftNAS Questions

Yes, SoftNAS uses reservationless ZFS snapshots.

Yes, you can create any other user on softnas and still be able to login to the UI with full privileges. However, you must first add the user to the 'softnas group'. 

Yes. SoftNAS patented SNAP HA® delivers a low-complexity solution for high-availability clustering that is easy to deploy and manage. A robust set of HA capabilities provides constant access to your data even when datacenter infrastructure failures such as datacenter, server, network and storage system failures to keep your business running without storage downtime.

Yes, SoftNAS Cloud NAS is delivered as a Virtual Storage Appliance and runs as a virtual machine on Amazon EC2, Microsoft Azure or VMware vSphere.

Yes, SoftNAS supports SCSI-3 persistent reservations.

SoftNAS leverages the local ephemeral SSD storage and RAM in the instances for the caching system. It’s a great part of our solution because we can enable any combination of compute, caching and attached storage based on the wide variety of the cloud offerings. We encourage customers to customize based on their needs. As new instances come out or improve, we immediately encourage customers to make the change! This is impossible to achieve with the conventional on-premise storage model.

Not at all! SoftNAS StorageCenter™ is the easy-to-use, intuitive GUI to manage SoftNAS Cloud NAS. The management software is accessed via your web browser and provides simplicity for creating standard mounts, including NFS, CIFS, and iSCSI storage volumes, which can be pooled into RAID backed arrays to customize redundancy and performance as well as setting advanced features.

If the copy replication is broken the, upon restart the copy resumes from the last known good snapshot.  DeltaSync takes place after a fail over event which only copies the differences since the node was active.

ZFS snapshots are based on tree snapshots which are stored considerably different than how block snapshots were traditionally done. The Copy On Write file system creates a map as to where the changed blocks are stored instead of traditional method of what was overwritten. This gives the ability to have unlimited snapshotting and facilitates the benefit of the little or no space that current ZFS snapshots consume. The below Article from Jeff Bonwick of Sun gives a great visual depiction of how tree snapshots are structured.

SNAP HA™ monitors all critical storage components, ensuring they remain operational.  When there is an unrecoverable failure in a system component, another storage controller detects the problem and automatically takes over ensuring no downtime or business impacts occur.

You can refer to the below section for more information: High Availability: All Platforms

We leverage AES 256 via LUKS. You can find more information on this subject here:

The ZFS Intent Log (ZIL) absorbs bursts or steady streams of incoming, synchronous write operations by rapidly recording the writes in high-speed, mirrored SSD storage, then returning quickly to the caller. This makes synchronous writes  operate at maximum speed. Later, when there is less I/O overhead, the writes which are cached in the ZIL are written to long-term pool storage. The ZIL is flushed every 5 seconds 

On AWS some customers use a small (5 GB) Provisioned IOPS SSD (never direct attached ephemeral SSD) to absorb massive write bursts. It does not need to be large because it only buffers a small timeframe of data.

Windows Failover Cluster requires a special block size and must be set manually:

  1. Use iSCSI as the storage protocol on SoftNAS, iSCSI Initiator on the MS servers.
  2. You have to create the pools via the GUI, but create the volumes via cli to get this.

         Example below using a 40G volume and thick provision:

          zfs create -V 40G -b 4k pool01/iscsi01 (crate the vol with a 4k block size)

          zfs get volblocksize pool01/iscsi01 (verify)

          zfs set reservation=40G pool01/iscsi01 (set the reservation size)

         zfs get reservation pool01/iscsi01 (verify)

         zfs list (verify)

    3. Format the volumes to have 4k block size for NTFS. (ZFS uses 128k by default)

The below command will list the 15 directories with the highest disk usage. The -x option will make it only search the root file system and ignore any other mounted systems specially ZFS pools, as scanning them may take long time and affect the performance.

du -xh / 2>/dev/null | sort -h -r | head -n 15

If you would like to check for a certain pool, you can replace "/" with "/Your-Pool"

We can put a pair of HA enabled nodes on premise for local storage and connect to Azure/AWS for cloud capacity. We do indeed enable replications and/or snap shots to the Azure/AWS hosted instances. Separate shares on Azure/AWS can be used for expanded capacity.

SoftNAS  encrypts your data while it is at-rest and also when it is in transit—we call it 360-degree encryption. SoftNAS believes that each business or organization should control the keys to their data—so only you have the encryption keys, not SoftNAS nor your underlying storage cloud platform provider.

Yes, we a CentOS based for our ZFS implementation (not Illumos… thank goodness).

We use two nodes for a high availability (HA) solution. The performance scales by changing the instance's type rather than node scale out. We can attach to a combination of back end storage options (block and object) for up to 16PB of capacity as well.

The SnapReplicate® feature provides block-level replication between two SoftNAS instances. SnapReplicate between source and target SoftNAS instances sends all data through encrypted SSH tunnels and authenticates using RSA PKI. Data is encrypted in transit using industry-standard ciphers. The default cipher for encryption is Blowfish-CBC, selected for its balance of speed and security, but you can use any cipher supported by SSH, including AES256-CBC.

Feel free to use the bench marking tool that you want that allows you to best represent your exact work load Read/Write percentage.

RPO is an acronym for Recovery Point Objective which refers to the most recent point in time for which you will be able to recover.  SoftNAS has a default RPO of 60 seconds. i.e. After the initial synchronization of data between two SoftNAS nodes, SnapReplicate will sync changes between SoftNAS appliances every 60 seconds.  Provided the amount of changed data over the past 60 seconds completes its transfer prior to the next sync your RPO is equal to that target. (The network and compute may be adjusted based on actual needs to keep RPO as low as possible).

RTO is an acronym for Recovery Time Objective or the amount of time required to recover from a failure. SoftNAS employs various mechanisms to enable customers to quickly recover from accessibility issues.  This recovery ranges from manual efforts to automated HA events.  Depending upon the architecture of the system, the nature of the ‘event’ RTO can be as low as 30 seconds.

There is a 7 day grace period where everything will continue to function to allow you to purchase a new license without interruption.

Once the 7 day grace period expires, you should expect the following:

  1. Scheduled snapshots will stop taking place.
  2. Replication will stop.
  3. HA will deactivate but the VIP will remain associated to the source node so that clients can continue to access the volume mount points.
  4. You will lose Storage Manager administrative access.
  5. Only two pages will function in Storage Manager.
    1. Licensing console. This allows you to enter your new license information once you have it procured.
    2. Software Updates console.

Your data remains intact and undisturbed. When SoftNAS is not running, NAS clients connecting via NFS, iSCSI, or CIFS will not have access to NAS services, which will be restored when the SoftNAS is powered back on. If data is in production with SNAP HA®, a failover would occur and the data would still remain available.

SoftNAS supports SMB v3 and NFS v3 and v4.

Our admin interface, Storage Center, is web based. It’s on either node and it unifies multiple SoftNAS deployments.

Open Source software can be enhanced by a wealth of programmers, which means bugs are easier to find and fix, and the software is much more secure. Although SoftNAS  is not Open Source, it is based on trusted Open Source industry standard software–Linux and ZFS–which allows an open and free architecture, so your data is never locked into one platform.  


The latest major release of SoftNAS is SoftNAS 5.  For the latest release number see Release Notes. There you will find notes on the latest release, and any fixes or improvements to the product.

Yes, you can have any number of EC2 instances with shared access to iSCSI targets and LUNs, NFS volumes and Windows CIFS shares. File locking and user permissions are maintained, so application operate as expected with a file server.

Yes, you can use the built-in SnapReplicate™ feature to replicate data changes from one availability zone (or AWS region) to another, for high-availability and added disaster recovery protection. You can use any backup tool which supports Linux and AWS to perform a separate backup, as well. SNAP HA® high-availability (HA) allows for 99.999% per year uptime.

It depends on your workload and performance needs. Please refer to AWS EC2 System Requirements and Amazon EC2 Setup and Performance Considerations.

Yes, support for Azure Active Directory (Azure AD) is supported by SoftNAS.

No, the price for SoftNAS is only for the subscription of SoftNAS and not for the storage and compute costs of Microsoft Azure infrastructure.

Customers can get a 30-day free trial. Subscription based hourly pricing and SoftNAS simplicity make it easy to deploy a NAS/SAN in the Cloud.

SoftNAS employs an active-passive HA pairing with both VM’s residing in an Azure Availability Set for maximum uptime. If one VM goes down, the other takes over. This configuration ensures that during either a planned or unplanned maintenance event or unexpected hardware failure, at least one virtual machine will be available and meet the 99.999% per year uptime Azure SLA. We replicate between the two for delivering our No Storage Downtime Guarantee.

Our current HA solution relies on the replication of data between instances. The SoftNAS SNAP HA® feature is based on an active-passive pairing of instances with a 60-second asynchronous data replication cycle. The storage that SoftNAS presents (i.e. block or blob) does not alter this requirement.

SnapReplicate™ provides block-replication between two SoftNAS controllers. SnapReplicate can be used for backup purposes, to create a hot-spare for failover and disaster recovery as well as for site-to-site data transfers. In Azure, SnapReplicate provides data replication between Geo-Redundant Storage (GRS).

SoftNAS as a software-defined NAS solution utilizes the compliance already implicit in the cloud provider’s infrastructure. Microsoft's Azure platform is housed on infrastructure that meets key international and industry-specific compliance standards. Microsoft supplies the specifics about its security and compliance programs, including audit reports and compliance packages. The Microsoft Trust Center also provides the ability to view compliance based on service, location and industry SoftNAS also integrates with the customer's existing Active Directory infrastructure for user authentication and access control and also provides the ability for data to be encrypted using AES-256 Cryptography.

SoftNAS provides various capacities on Azure depending on the backend data store utilized. SoftNAS leverages data stores available via Block (Standard or Premium). The following are the maximums (based on current Azure offerings):

  • For Block storage: Capacity limit is determined by the instance size. Capacity limits = 2TB disks x Core count. The instance size determines the core count. The current maximum limit for Azure is 40TB.

It depends on your workload and performance needs, please refer to Microsoft Azure System Requirements.

SoftNAS supports NFS, CIFS/SMB, and iSCSI file service protocols as a POSIX file system. Advanced features include: cross-zone and cross-region replication, data compression, deduplication, thin-provisioning, data encryption (at rest and in transit), data protection, snapshots, rapid rollback capability and more.

Yes, it does support both of these.  If there are additional questions regarding what SoftNAS supports on VMware, please feel free to contact us.

You can use the built-in SnapReplicate™ feature to replicate data changes from one site to another, for high-availability and added disaster recovery protection. You can use any backup tool which supports Linux to perform a separate backup as well. SNAP HA® high-availability (HA) allows for 99.999% per year uptime.

It depends on your workload and performance needs. Please refer to VMware vSphere System Requirements.

Moving to SoftNAS 5

Buurst is excited about our SoftNAS 5 release and we think you will be too. To help you understand the value and key points of moving from SoftNAS 4 to SoftNAS 5, we have created this SoftNAS 5 FAQ to quickly get you the information you need to help with your move to SoftNAS 5.

For a more comprehensive list, please see the SoftNAS Release Notes

  • SoftNAS 5 is now running CentOS 8.2
  • SoftNAS 5 is now running a newer kernel
  • SoftNAS 5 has an updated Samba server for CIFS/SMB
  • Enhanced performance
  • CentOS 8.2: Previous versions of SoftNAS used CentOS 6, which has reached end of support. Thus, CVE and other fixes to CentOS 6 are no longer being provided. CentOS 8.2 is supported and provides the ability to obtain CentOS updates and patches allowing for better support of your SoftNAS environment.
  • New kernel and Samba: Moving to CentOS 6 also allowed us to use new versions of the kernel and Samba. As a result of the newer components, and a few other modifications we made, we are seeing measurable performance gains in SoftNAS 5. In certain scenarios with the new Samba, we have seen a specific benchmark that achieved a 60% gain in performance. While you may not see this level of improvement for every scenario, we do see measurable improvements across the board in our SoftNAS 4 vs SoftNAS 5 benchmarks. 
  • Also note that moving to SoftNAS 5 now will help ensure that you are still within the Buurst End of Support policies. The official End of Support for SoftNAS 4, by policy, is scheduled for January 2022.

No, 1-click upgrade from SoftNAS 4 to SoftNAS 5 is not supported. Due to the changes in SoftNAS 5 with the new CentOS Linux, you will not be able to use 1-click upgrades.

No, 1-click upgrade from SoftNAS 4 to SoftNAS 5 is not supported. Due to the changes in SoftNAS 5 with the new CentOS Linux, you will not be able to use 1-click upgrades.

  • To move from SoftNAS 4 to SoftNAS 5, the first step is to open a ticket with our Buurst Support team to plan and schedule time to have them assist you with your move. The Support team is here to help you ensure a quick and successful move to SoftNAS 5.
  • The Buurst Support team has a simple-to-use tool to automate the move to SoftNAS 5 that is based on years of experience with manually performing such migrations to new SoftNAS instances and VMs.
  • The process is straight forward using the tool:

    • Schedule a maintenance window to ensure all activity to the existing SoftNAS servers is quiesced. The tool we use will also double-check that the system is in a state ready to move to SoftNAS.

    • Once the existing SoftNAS 4 systems are quiesced, the disk devices attached to SoftNAS 4 systems will be detached.

    • New SoftNAS 5 systems will be started in the cloud and the configuration data from the SoftNAS 4 systems will be moved to the new SoftNAS 5 systems.

    • The detached disk devices will be attached to the new SoftNAS 5 systems (no manual copy of the data to new storage devices is required. It is rather a detachment of disk devices from SoftNAS 4 and attachment of the same disk devices to SoftNAS 5.

    • If SoftNAS was running in an HA environment, the HA configuration is re-established on the new SoftNAS 5 environment, including moving the virtual IP, so existing NFS and CIFS mount point continuity is maintained with no unmount/remount required by clients.

    • All the details of the process will be explained to you by our Buurst Support team to ensure you clearly understand the process in the planning phase of the effort.

First, please contact Buurst Support. They will work alongside you to ensure you have a frictionless experience.

There are several reasons to move off the older versions of SoftNAS and on to SoftNAS 5 including:

  • Performance improvements of up to 60% have been benchmarked for certain workflows
  • Azure OMS and OMS Azure Extensions are now supported
  • Improved baseline security
  • Upgrade process improvements that no longer checks and interrupts the process based on SnapReplicate version differences on paired instances
  • Samba updated to version 4.12.10-15
  • Linux version change from CentOS 6.9 to CentOS 8.2 ensures security and other Linux fixes continue to flow normally as expected.

You need to contact Buurst Support to perform the move to ensure it is successful. They will work alongside you to complete the move.  In the event something arises, Buurst support will be there to address it.

Yes, most moves to SoftNAS 5 take less than 30 minutes to complete. Buurst Support will be able to provide additional guidance specific to your configuration.

Yes, because new SoftNAS 5 instances are created, and the actual disk devices are moved and connected to them, the original SoftNAS instances/VMs still exist and in the event a surprise issue arises, the disk devices can be easily moved back and reset back to their original configuration.

Buurst wants to make sure everyone that is moving from SoftNAS 4 to 5 has a smooth transition. Buurst Support will help to ensure all your specific configuration and system states are migrated correctly.

Buurst supports up to 2 major releases back.  However, with the retirement of the CentOS 6 distribution, we recommend everyone move to the SoftNAS 5 release for the later, supported version of CentOS, and the related patch and CVE fixes that come with it.

It depends, we can support SoftNAS specific bugs and other issues, however due to the retirement of CentOS 6 CVEs specific to the underlying Linux OS cannot be addressed. Therefore, we recommend everyone move to SoftNAS 5 as soon as practical.

No, all new feature development will be focused solely on SoftNAS 5.

Contact Buurst Support and they will work with you to ensure the migration is completed in the minimum amount of time and ensure the data transferred is intact.

Yes, as with any new server deployment, this is a standard process that needs to be performed. These applications should not have any installation issues, provided they support and are supported by CentOS 8.

No, please work with Buurst Support to ensure replication states are maintained. You will not have to re-seed from scratch after the SoftNAS 5 move.

  • No, your instance/VM IP addresses will change with the move to SoftNAS 5.
  • Yes, your Virtual IP (VIP) addresses will remain the same.
  • Buurst Best Practice recommends using DNS instead of using direct IP access.

Yes, any time you deploy a new SoftNAS instance/VM you will have to join that new computer to the Active Directory Domain from a security administration perspective.

  • No labels