ZFS HA Plugin


ZFS is a combined file-system and logical volume manager designed by Sun Microsystems. The features of ZFS include protection against data corruption, support for high storage capacities, integration of the concepts of filesystem and volume management, snapshots and copy-on-write clones, continuous integrity checking and automatic repair, RAID-Z and native NFSv4 ACLs. ZFS is implemented as open-source-software, licensed under the Common Development and Distribution Licence (CDDL). The ZFS name was a trademark of Oracle until September 20, 2011. ZFS has since been widely adopted and integrated with many Operating Systems including OpenSolaris, OpenIndiana, Illumian, FreeBSD and various Linux variants.

ZFS is also now widely used as the core file-system deployed in many Open Storage Appliances, but lacks some Enterprise features, including High Availability and Failover to provide resilience against failure. Enter RSF-1. ZFS + RSF-1 = Highly Available Open Storage

[Read RSF-1 for Storage Concept Guide]


RSF-1 brings advanced HA (High Availability) features to ZFS providing a more resilient and robust storage offering tolerant to system failures. Active/Active and Active/Passive configurations are supported. As well as providing core ZFS HA and failover capability to ensure availability in the event of failure, RSF-1 also brings ring-fencing mechanisms to protect multi-tenanted storage devices, orchestrates the seamless failover of COMSTAR and ALUA targets, and manages virtual network access (views) to the data.

<Read RSF-1 High Availability for Storage Data Sheet>


Each RSF-1 node in a ZFS cluster (1-64 nodes), communicates with all other RSF-1 cluster nodes via a number of heartbeat channels, and manages the availability of up to 200 ZFS pools. Each RSF-1 service, generally supported with at least one VIP and ZFS pool, can be failed over to any other ZFS server that has been configured with shared storage and networking available. Each RSF-1 service and ZFS controller can be set for automatic or manual (planned) failover.

ZFS Failover can be localized (within a single dual-controller chassis) or using RSF-1 Stretch Cluster capability, between nodes over a wider geographical area (network and bandwidth availability dependent).

RSF-1 clusters can be managed and administered from command-line or GUI and can be optionally integrated with vendors own services using the RSF-1 APIs.

Features RSF-1 Capabilities
History First released in 1996 on Solaris and Linux. Proven and deployed on thousands of enterprise-grade critical systems worldwide.
Technology C, C++ with Unix shell interfaces, no kernel drivers
Design Philosophy Easy to understand through it’s simplicity of design. Unix-like
Platform Support Solaris, Open Solaris / Open Indiana / Illumos, Linux, FreeBSD, Mac OSX
Hardware Support Hardware agnostic. Virtualised server compatible.
HA topology Active-Active, Active-Passive in 1-64 way configuration
Installation Options Fresh Operating System installation, or back-fit options
File System Support ZFS, UFS, XFS, EXT4, VxFS, SVM
Controller / Nodes Topology support 1-64
Services Supported 1-200
Heartbeat Mechanisms Public network, private network, serial, shared disk, cloud beacons (for “stretch” configurations)
Failover Options Controller and service specific Automatic or Manual
Geographic Topologies In-chassis to “stretch” depending on network configuration and bandwidth availability
Detection Time Sub-second detection; overall failover time dependent on application / storage
Disk Fencing Protections MHD SCSI-2 Reservation / panic, STONITH integration
Network Availability Intelligent networking monitoring integrated with service failover
RSF-1 Operation Command-line, GUI, API, Web
API Services C, C++, SWIG (Java, Python, Perl  etc)
VIP Support 0-N VIPs per service
Application Agent Availability Oracle, MySQL, Ingres, Sybase, NFS, Samba, httpd, JDBC, Port Monitor
Application Agent Framework Flexible Java / Script toolkit for other applications
ZFS Specific Support
COMSTAR / ALUA Cluster Support Integrated STMFHA for managing iSCSI/ALUA target groups within cluster
ZFS cache file synchronization Speeds ZFS pool(s) failover time
vdev heartbeat Non-destructive RSF-1 (disk) heartbeats through ZFS pool vdevs
Parallel Pool Import / Export Speeds ZFS pool startup and failover
RSF-1 Integration Options
GUI Support API access with C, C++, SWIG (Java, Python, Perl etc)
Licensing Integration Automatic licensing server integration – Flexible framework
Commercial Considerations
Licensing Timed evaluation licenses, Permanent  (perpetual) “bought” licenses
Pricing Model Flexible volume / tiered pricing
Branding Optional “white label” / OEM opportunity
Penetration The “de facto” HA plugin widely used by many ZFS open storage vendors.