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Managing SAN Devices and Multipathing in Oracle® Solaris 11.3

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Updated: March 2018

SAN and Multipathing Glossary


A flow control mechanism enabled on the Ethernet interface to ensure consistent, lossless Ethernet transport. 802.3x is also known as PAUSE.


(Access Control List) A security model based on NFSv4 specifications to protect ZFS.

advanced format disk

A hard disk drive larger than the traditional 512-byte block size supported by the Oracle Solaris operating system.

AF disk

See advanced format disk.

anonymous memory

Physical memory pages that contain the mappings of physical files to virtual addresses and are backed by swap space. These memory pages are called anonymous because no identity is assigned to the swap space that backs them.

asymmetric storage device

A storage device in which paths to the storage device may have different access states. For example, active and standby paths, or active and optimized paths.


(AT Attachment Packet Interface) An interface between a computer and its CD-ROM drives and tape backup drives. ATAPI provides the additional commands the computer uses to control such drives with IDE interface and controllers.

attribute-aware option

A command option that can be used to query, copy, or find file attributes, thus enabling Oracle Solaris file system commands to support file system attributes.


Dynamic, boot-time configuration of the kernel by itself during which it determines the devices attached to the system. It also identifies the modules, such as drivers, needed by the devices, and loads those modules into memory.


A client-side service that enables a system to automatically mount and unmount NFS resources whenever they are accessed. The resource remains mounted as long as the user is using a file in that resource. If the resource is not accessed for a certain period of time, it is automatically unmounted.

bit rot

The deterioration of bits stored on disks that occurs due to various causes such as magnetic influences and cosmic rays and that can cause potential data corruption in large or long-running systems.

bit-masking format

A format, also known as the Version1 format, that is used to tune the parameters of disk drivers.

boot environment

A boot environment (BE) is a ZFS file system that is designated for booting. A boot environment is essentially a bootable instance of the Oracle Solaris OS image or any other software packages that are installed into that image.


A computer program that loads an operating system on a computer.


(contract file system) An interface for creating, controlling, and observing contracts. A contract enhances the relationship between a process and the system resources. It provides richer error reporting and optionally, a means of delaying the removal of a resource.

cache device

A storage device used to cache storage pool data. Cache devices provide an additional layer of caching between main memory and disk. Using cache devices increases performance of random-read workloads of mostly static content.


(Converged Enhanced Ethernet) The pre-standard Converged Enhanced Ethernet (CEE) DCBX specification v1.01 used by the Oracle Solaris operating system, along with the IEEE 802.1qaz DCBX specification, enables interoperation with a larger set of switches when using Data Center Bridging (DCB).

character device interface

See raw device interface.


A 256-bit hash of the data in a file system block. The checksum capability can range from the simple and fast fletcher4 (the default) to cryptographically strong hashes such as SHA256.


(common Internet file system) A standard way a computer user share files across intranets and internet.


A writable volume or a file system whose initial contents are the same as the dataset from which it was created. Clones can be created only from a snapshot. As with snapshots, creating a clone is nearly instantaneous and initially consumes no additional disk space because a clone initially shares all its disk space with the original snapshot. As changes are made to the clone, it uses more disk space. In addition, you can also snapshot a clone. See also snapshot.


(converged network adapters) Adapters that transfer Ethernet and FCoE traffic. CNAs convert FCoE traffic into FC traffic, which is then sent to the connected SAN over the FC network.

common Internet file system

See CIFS .


(Common Multiprotocol SCSI TARget) A software framework that enables you to convert any Oracle Solaris host into a SCSI target device accessible over a storage network by initiator hosts. This means you can make storage devices on a system available to Linux, Mac OS, or Windows client systems as if they were local storage devices. For more information, see target, and initiator.

Converged Fabrics

The sharing of the same Ethernet network by multiple computing entities such as storage devices, networking, clusters, and system management traffic.

converged network adapters

See CNAs.

crash dump

A part of the hard drive which stores the raw data generated at the instant of a computer program crash. The data is important to diagnose problems with the crashed program. Dump files can safely be deleted after diagnosing and resolving the problem causing the program crash. When an Oracle Solaris system is installed, a dump volume is created automatically, and can later be reconfigured. A crash dump device is also called a dump device, memory dump, or a system dump.

data resilvering

A process of moving data from a replaced device to the new device, which is a part of scrubbing. For example, if a mirror device is replaced or taken offline, the data from an up-to-date mirror device is copied to the newly restored mirror device. When resilvering is needed, other forms of data scrubbing are interrupted, and restarted only when resilvering is completed. In traditional volume management products, this process is referred to as mirror resynchronization. See also data scrubbing.

data scrubbing

A mechanism to perform automatic, routine checking of all inconsistencies, commonly used in memory and other systems as a method of detecting and preventing errors before they result in a hardware or software failure.

data striping

Storing of logically sequential data, such as a file, as segments on multiple physical storage devices such that data segments across multiple devices can be accessed concurrently, to result in faster data access.


A generic name for the following ZFS components: clones, file systems, snapshots, and volumes. Each dataset is identified by a unique name in the ZFS namespace.


(Data Center Bridging Exchange) The IEEE 802.1qaz specification is used by the Oracle Solaris operating system along with the pre-standard Converged Enhanced Ethernet (CEE) DCBX specification v1.01, to enable interoperation with a larger set of switches when using Data Center Bridging (DCB).


The process of eliminating duplicate blocks of data in a ZFS file system. After removing duplicate blocks, the unique blocks are stored in the deduplication table.

deferred dump

A mechanism to retain crash memory across system reboots to enable the writing of a crash dump after system reboot. When the system reboots, the core dump is written to the file system defined in the dump configuration, and preserved for later analysis of the issue causing the crash. The system can reboot again once the dump is written.

delegated administration

A ZFS system of refined permissions for specific users, groups, or everyone. Two types of delegated permissions are supported:

  • Individual permissions that can be explicitly delegated such as create, destroy, mount and snapshot.

  • Groups of permissions called permission sets that are updated in a way that causes the update to apply to all consumers of the permission set.

Device Detection Tool

(Oracle Device Detection Tool) A tool that detects whether Oracle Solaris can be installed on an x86, x64, or a SPARC system. If your device is already listed in the Oracle Solaris OS Hardware Compatibility List (HCL), you do not need to use this tool. See also HCL.

device hierarchy

A collection that is comprised of the physical and logical namespaces of the devices connected to a system and is created at the first system boot. The kernel uses device hierarchy to associate drivers with their devices.

discovery method

The way in which the iSCSI targets are found by iSCSI initiators. The three discovery methods are:

  • Internet Storage Name Service (iSNS) – Potential targets are discovered by interacting with one or more iSNS servers.

  • SendTargets – Potential targets are discovered by using a discovery address.

  • Static – Static target addressing is configured.

disk label

A disk label stores information about the disk's controller, geometry, and slices. See also VTOC label.

disk slices

A group of sectors on a disk to which one file system on the disk is assigned. Each disk slice appears as a separate disk drive, and no file system can span multiple slices. A slices is also called a partition.

domain mode

A mode of operation of the Oracle Solaris SMB server. See also SMB .


(dynamic reconfiguration) The adjustment of the configuration of hot-pluggable components by the system, and the moving or disabling of hardware and software system resources without physically removing them from the system. See also hot-plugging.

dump device

See crash dump.

dynamic discovery

The software automatically recognizes devices and any modifications made to device configurations. This feature makes devices available to the system without requiring you to reboot or manually change information in configuration files.

dynamic striping

The striping of data at write time across all top-level virtual devices by ZFS in a way that prevents the creation of fixed-width stripes at allocation, and supports stripes of varying widths. See also data striping.

dynamic reconfiguration

See DR.


(Extensible Firmware Interface GUID Partition Table) A disk partitioning method enabling all of the disk space on the boot device to be used for an Oracle Solaris installation. The Oracle Solaris installation program can install an EFI (GPT) disk label on a ZFS root pool disk by using DVD, USB, and automated installation methods. EFI(GPT) labels are used for disks smaller than 2 terabytes.

EFI disk label

A type of VTOC label for disks larger than 2 terabytes. See also VTOC label.

EoIB device

(Ethernet over IB device) A device enabling the transport of Ethernet frames over IB fabric. See IB.

EUI address

(extended unique identifier) An address that identifies a class of GUIDs and is used in both the SCSI and InfiniBand standards.

failover support

In the context of Oracle Solaris I/O multipathing, failover support is the management of the failure of storage paths through redundant host connectivity, the use of secondary paths to maintain host I/O connectivity to storage devices.

Fault management framework

A utility that flags devices as faulty, and allows the faulty devices to be safely and automatically inactivated to avoid data loss, data corruption, system instability and system down time. Critical devices are never retired.

FCoE hardware offload

The reduction of CPU utilization in FCoE networks by the use of inbuilt processors in the converged network adapters (CNAs) used to transfer the FCoE traffic.


(File Descriptor File System) Virtual file system that provides explicit names for opening files by using file descriptors.


(First-in, First-Out File System) Virtual file system consisting of named pipe files that give processes common access to data.

file system

A hierarchical structure of directories used to organize and store files. Oracle Solaris supports the following three file system types:

  • Disk-based – Stored on physical media such as hard disks and DVDs

  • Network-based – Usually stored on a server, and accessed by other systems on the network

  • Virtual – Usually stored in memory that does not occupy file system disk space, and provides access to special kernel information and facilities


Fault Management Architecture. See Fault management framework.

format utility

The central Oracle Solaris tool for administering disks through a range of tasks from discovering the types of disks to verifying that these disks are known to the system.

Free Hog Slice

A temporary slice created to accommodate the resizing of one or more disk slices by the format utility. This temporary slice expands into the discarded space when you shrink a slice and shrinks to donate the space needed to expand a slice. The Free Hog Slice exists only during installation or when you run the format utility. See also format utility.


A file system monitoring tool to report file system operations. You can report the operations by various options, such as by mount point or by file system type.

full stream

A stream format that consists of all dataset content from the time that the dataset was created up to the specified snapshot. See also snapshot stream.


A network device driver framework that provides APIs to be used in the creation of device drivers.

global zone

A global zone is both the default operating system, and the zone used for system-wide administrative control. All processes run in the global zone if no non-global zones are created. Non-global zones, or simply zones, are configured inside the global zone. A non-global zone cannot detect the existence of any other zone. See also zone .


(GNU Object Model Environment) A free, open source desktop for UNIX operating systems.


(GRand Unified Bootloader) A legacy boot loader used prior to the GRUB 2 boot loader. Note the difference between GRUB and GRUB 2. See also GRUB 2.


(GRand Unified Bootloader 2) A more powerful and modular boot loader than GRUB, that supports a wider range of platforms and firmware. Unlike GRUB, GRUB 2 places many facilities in dynamically loaded modules, which enables the core GRUB 2 image to be smaller and therefore loads faster and is more flexible. As a result, GRUB 2 functionality can be loaded on demand at boot time.

Hardware Compatibility List

A list of devices compatible with Oracle Solaris. If your device is not on this list, use the Oracle Device Detection Tool to determine if your device is compatible with Oracle Solaris. See also Device Detection Tool.

hardware offload

See FCoE hardware offload.

HCA_SVC device

Device that binds a communication service to a specific HCA.


See Hardware Compatibility List.


(Human Interface Device) A device controlled by humans to operate computer systems, such as keyboards, mice, trackballs, and joysticks. Such devices also include front-panel controls such as knobs, switches, and buttons.

holding a snapshot

A ZFS feature preventing a snapshot from being inadvertently destroyed. Destruction of snapshots may lead to failure of ZFS send and receive operations. Placing a hold on a snapshot prevents it from getting destroyed inadvertently. In addition, this feature allows a snapshot with clones to be deleted only upon the removal of the last clone.


Adding, removing, replacing or configuring system components or devices on a running system. Hot-pluggable bus types include USB, Fibre Channel and SCSI. Hot-pluggable devices include PCI, PCIe, USB and InfiniBand. Hot-plugging is also called dynamic reconfiguration (DR). See also DR.

hot spares

A feature enabling you to identify disks that could be used to replace a failed or faulted device in a storage pool. A hot spare device is inactive in a pool until the spare replaces the failed device. A hot spare device must be equal to or larger than the size of the largest disk in the pool.


(High Sierra File System) Read-only file system, used on CD-ROMs and DVDs. Oracle Solaris supports file systems created according to ECMA-119, ISO 9660:1998 or ISO 9660:1999 with Rock Ridge and Joliet extensions. The extensions provide additional features and attributes to files such as long file names (up to 255 characters) and UNIX permissions and attributes.

Human Interface Device

See HID.

hybrid storage pool

The ZFS hybrid storage pool, available in Oracle's Sun Storage 7000 product series, that combines DRAM, SSDs, and HDDs to improve performance and increase capacity, while reducing power consumption.

I/O load balancing

A method of maximizing system performance by routing I/O through multiple host connections, thus spreading the I/O load.


(InfiniBand) An I/O technology based on switched fabrics that provides a high bandwidth and low latency interconnect for attaching I/O devices to hosts and for host-to-host communication. IB devices are managed by the Oracle Solaris IB nexus driver. Oracle Solaris supports the following IB devices and technologies: IPoIB, EoIB, SDP, RDSv3, RDS, NFSoRDMA, iSER, uDAPL, and OFUV.

IB nexus driver

A driver that queries the Solaris IB Device Manager (IBDM) for communication services to enumerate various IB devices.

IB partition link

A new part class of data link used for data transfers and managed by using dladm subcommands. You can create an IB partition link on top of an IB physical link, one per each partition key on the port.

IB port device

A device that binds a communication service to a specific port of a Host Channel Adapter (HCA).


(Oracle Solaris InfiniBand Device Manager) A communications service provider queried by the IB nexus driver for services to enumerate various IB devices.


The property of a ZFS file or directory that allows only read-only access to the file or directory and thus prevents it from being changed.

incremental stream

See snapshot stream.


See IB.

initiator group

A set of initiators.

Internet Protocol over Fibre Channel

The implementation of IP (internet protocol) over FC (Fibre Channel) fabric in a network.

Internet Storage Name Service

A dynamic target-discovery method. See also dynamic discovery.

I/O multipathing

an integral part of the Oracle Solaris storage stack, provides multiple access paths for systems running the Oracle Solaris operating system (OS). Oracle Solaris I/O multipathing is based on the open standards for communicating with devices and device management, ensuring interoperability with other standard-based devices and software. Multipathing provides higher availability for storage devices. For high availability, the storage devices use the I/O multipathing feature to ensure that the secondary path is online when the primary path of the device goes offline. Oracle Solaris multipathing was previously known as StorageTek Manager software.


See Internet Protocol over Fibre Channel.

IPoIB device

(IP over IB device) A device enabling the transport of IP packets over IB connections. See also IB.


(iSCSI Qualified Name) The unique identifier for a device in an iSCSI network.


(iSCSI Extension for RDMA) A protocol that accelerates the iSCSI protocol by mapping the data transfer phases to Remote Direct Memory Access (RDMA). It allows data transfer directly between the iSCSI nodes without intermediate data copies. iSER is useful for enhancing networks providing RDMA services, such as an InfiniBand network.

iSNS discovery

A dynamic target-discovery method. See also dynamic discovery.


A set of disks. Usually, a set of hard disks that are not configured to act as a redundant array.

jumbo frames

A capability that reduces the number of frames needed to transfer data in Ethernet transactions by supporting frames sized larger than 2.5 Kilobyte.

Kerberos V5

Kerberos is the primary security protocol for mutual authentication within a domain. The Kerberos V5 protocol enables the user and server to mutually authenticate.

labeled file system

A label policy and implementation that marks files and file systems as sensitive by applying labels.


(loadable kernel module) A software component that is automatically loaded by the kernel to perform a specific task on the system, for example, a device driver that is loaded when the device is accessed. Oracle Solaris allows you to customize how kernel modules are loaded.

loadable kernel module

See LKM.

local login

The local authentication of users requesting shared resources by the Oracle Solaris SMB server operating in workgroup mode. See also SMB .


(Loopback File System) Allows to create a new virtual file system so that you can access files by using an alternative path name. For example, you can create a loopback mount of the root (/) directory on /tmp/newroot. This loopback mounts and the entire file system hierarchy appears as if it is duplicated under /tmp/newroot, including any file system mounted from NFS servers. All files will be accessible either with a path name starting from root (/), or with a path name that starts from /tmp/newroot.

log device

A storage device, such as an NVRAM or a hard disk, dedicated to providing blocks for the ZFS intent log (ZIL), provided to satisfy POSIX requirements for synchronous transactions. Better performance might result if log devices are used for ZIL instead of the main storage pool.

logical unit

A finite set of available resources, such as the amount of data that can be stored and the number of active commands that a device can process at a time. SCSI storage arrays present storage to a system in the form of a logical unit.

Loopback File System



See logical unit.

LU mapping

A mapping that enables an LU to be accessed in iSCSI, Fibre Channel, and FCoE configurations. LU mappings are of two types:

  • Simple mapping – Exposes the LU to all initiators through all the ports, using one command.

  • Selective mapping – Enables you to specify the hosts that can access the LU.


See LU.

LZ4 algorithm

A compression algorithm that achieves a higher compression ratio with better system performance while saving more disk space than the default ZFS compression.

mirrored pool

A mirrored storage pool configuration requires at least two disks, preferably on separate controllers. A mirrored configuration can be simple or complex, where more than one mirror exists in each pool.


(master boot record) A legacy partition format based on PC DOS-based computer architecture used to partition disks smaller than 2 terabytes. Located at the start of the disk, the MBR partition contains the boot code and a table of four partition definitions. Because of the disk size limitation with MBR partitions, the newer GPT standard was developed. See also GNOME.

memory dump

See dump device.


A virtual device that stores identical copies of data on two or more disks. If any disk in a mirror fails, any other disk in that mirror can provide the same data.


(mnttab File System) A virtual file system that usually provides read-only access to the table of mounted file systems for the local system.

mount point

Point on the main file tree on which a portion of a file tree structure is mounted to make its files accessible to users.

mounting a file system

Connecting the file system sub-tree that is on a specific device to the file system tree.

named share

A share that inherits properties from the parent file system, which provides more flexibility in setting permissions and properties in an SMB environment.


(Name File System) A virtual file system used mostly by STREAMS for dynamic mounts of file descriptors on top of files.


(network-attached storage) A file storage server on a computer network enabling a heterogeneous group of clients to access the files. NAS thus provides dedicated network-attached storage, taking over the responsibility of serving files from other servers on the network, leading to faster file access, and simpler administration, and configuration.

network-attached storage

See NAS.


(Network File System) A network-based, distributed file system protocol used to provide remote access over IP to files or directories residing on a server by mounting them on remote clients. The server keeps a list of currently shared resources and their access restrictions (such as read/write or read-only access). NFS makes the actual physical location of the resource irrelevant to the user, and makes it unnecessary to place copies of commonly used files on every system. The advantage of using NFS in your network is that you can share file data across many systems.


(NFS over Remote Direct Memory Access) A capability for providing NFS services over IB using RDMA. See also IB, RDMA, and NFS.


(network interface card) A network adapter card that connects a computer to a network. Some NICs, such as the igb card, can have multiple physical interfaces.

non-global zone

See zone .


The attribute of a ZFS file or directory that prevents files or directories in ZFS from being deleted or renamed. The file itself can still be changed by applications or by users unless made immutable.


(N_Port ID virtualization) is a Fibre Channel facility that enables one FC adapter to have many N_Port IDs.


Non-Volatile Memory Host Controller Express.


(object file system) A virtual file system that describes the state of all modules currently loaded by the kernel. This file system is used by debuggers to access information about kernel symbols without having to access the kernel directly.


(OpenBoot PROM) A firmware installed on SPARC systems that enables the system to load an operating system from an installed hard drive, the DVD-dual drive, the network, or from an external boot device.


(Open Fabric User Verbs) The most popular InfiniBand OS-bypass framework, made available by the Open Fabrics Enterprise Distribution (OFED). See also IB.

Oracle Hardware Management Pack

Collection of cross platform components for hardware management included in the system/management package.

Oracle Solaris Cryptographic Framework

An encryption framework used in ZFS encryption. This framework automatically gives ZFS encryption automatic access to any available hardware acceleration or optimized software implementations of the encryption algorithms.


See disk slices.


See 802.3x.


(Personal Computer File System) A disk-based file system which allows read and write access to data and programs on DOS-formatted disks that are written for DOS-based personal computers.

per-property Inheritance

A sharing syntax for pool version 34 onwards, that makes use of ZFS property inheritance to ease share maintenance. Each sharing characteristic becomes a separate share property.


A logical group of devices describing the layout and physical characteristics of the available storage. Disk space for datasets is allocated from a pool.

process file system

A virtual file system residing in memory and containing a list of active processes, by process number, in the /proc directory. Information in the /proc directory is accessed and used by various commands, debuggers and other development tools using file system calls.


See process file system.

property inheritance

ZFS supports file systems organized into hierarchies, where each file system has only a single parent. The root of the hierarchy is always the pool name. ZFS supports property inheritance so that you can set common properties quickly and easily on entire trees of file systems by using hierarchies. An inheritable property is a property that, when set on a parent file system, is propagated down to all of its descendents.


(Oracle Solaris Cluster Proxy File System) Disk-based file system protocol used as a basis for the cluster file system provided by the Oracle Solaris Cluster software.

queue depth

Used for flow control. SCSI storage arrays present storage to a system in the form of a logical unit. A logical unit has a finite set of available resources, such as the amount of data that can be stored and the number of active commands that a device can process at a time. The number of active commands that can be issued before a device blocks further I/O is known as queue depth. With Oracle Solaris I/O multipathing, a single queue is created for each logical unit regardless of the number of distinct or separate paths it might have to the host.


(Oracle Real Application Clusters) A collection of interconnected computers or servers that appear to operate as a single server to end users and applications. Oracle RAC enables you to also cluster Oracle databases.


A virtual device that stores data and parity on multiple disks.

RAID-Z storage configuration

ZFS data-protection technology that has lower block overhead costs than mirroring.


(Reliability, Availability, and Serviceability)

  • Reliability - A reliable system helps avoid, detect and repair issues such as hardware faults and data corruption.

  • Availability - Highly available systems report less downtime, and stay operational even when faults occur.

  • Serviceability - Also called maintainability. Serviceable systems can be repaired and maintained through faster and simpler fault detection and resolution mechanisms that are minimally disruptive to normal system functioning. For example, the system makes an automated call to a service agent as soon as it experiences a fault.

raw data slice

A data slice typically created by third-party database applications. Raw data slices must not be created on block 0 or slice 2. Block 0 stores the disk label while slice 2 represents the entire disk with a VTOC label. Creating raw slices on these two locations overwrites the disk label and renders data on the disk inaccessible.

raw device interface

A logical device file that allows direct access to a storage device while bypassing the caches and buffers of the operating system. This helps software applications themselves manage data caching rather than using the data caching capabilities of the operating system. Raw device interfaces transfer only small amounts of data at a time. A raw device interfaces is also called a character device interface.


(role-based access control) Restricting access to computing systems and resources based on the roles users are accorded in an enterprise.


(Reconfiguration Coordination Manager) The framework that manages the dynamic removal of system components. By using an RCM script, you can register and release system resources with better control. See dynamic reconfiguration.

RCM script

See RCM.

Remote Direct Memory Access

A technology supporting the direct exchange of the data in the main memories of networked computers, bypassing, and thus freeing up resources such as the operating system, cache and processor of the computers.


See Remote Direct Memory Access.


(Reliable Datagram Sockets version 3) An RDMA interface required primarily for InfiniBand transport by Oracle for Oracle Real Application Clusters (RAC). See also RAC, IB, and RDMA.

read-only native properties

ZFS properties that cannot be inherited or set, but can only be retrieved.

Reconfiguration Coordination Manager

See RCM.

recursive stream package

A stream package that consists of the specified dataset and its descendants. Unlike replication stream packages, intermediate snapshots are not included unless they are the origin of a cloned dataset that is included in the stream. By default, if the origin of a dataset is not a descendant of the snapshot specified in the command, the behavior is similar to replication streams.


A ZFS feature provided through mirrored and RAID-Z configurations, and vital for preventing data loss and enabling the repair (self-healing) of data inconsistencies. Without ZFS redundancy, the pool can only report data inconsistencies, but cannot repair those inconsistencies.

remote replication

The process of copying a ZFS file system from a storage pool on one system to a storage pool on another system using the zfs send and receive commands without any special configuration or hardware. Although you can specify different levels of configuration for the newly created pool, such as RAID-Z, the data remains identical to the data in the original file system.

remote wakeup

A feature used by a device to notify the system to restore power to its path so that it can be used. The system can also be notified to restore power to the device when it receives an I/O request from an application.

replication stream package

A stream package that consists of the specified dataset and its descendants. It includes all intermediate snapshots. If the origin of a cloned dataset is not a descendant of the snapshot specified on the command line, that origin dataset is not included in the stream package. To receive the stream, the origin dataset must exist in the destination storage pool.


See data resilvering.

role-based access control


root pool

A ZFS pool that contains the boot file system.


An integrated hierarchical storage manager (HSM) and storage area network (SAN) file system. SAM is the HSM storage and archive management component. QFS is the SAN scalable high performance file system component. SAM-QFS also has integrated disk volume management and tape volume management. QFS also has a write once, read many times (WORM) file system capability. QFS can be used independently of SAM when just a file system is needed. SAM requires QFS and cannot be used independently of QFS.


(storage area network) A Fibre Channel network that provides server access to data stored at block level, so that storage devices seem locally attached to the operating system. These storage devices that form part of the SAN are usually not accessible to other devices on the wider local area network (LAN). Although a SAN provides only block-level operations, shared-disk file systems can be built on top of SANs to provide file-level access.

SAS device discovery

The process of detecting all the end devices and expanders connected to the SAS host.

SAS multipathing

A technology that provides higher availability by allowing data to use multiple paths to the arrays from Host Bus Adapters (HBAs) on the same server or on different servers.

SAS target

A hard disk or a storage array that has logical units and ports, and receives and responds to service and task management requests made by SAS initiators.


See data scrubbing.


(Sockets Direct Protocol) A protocol that supports sockets over IB. See IB.

selective LU mapping

See LU mapping.

self-contained recursive stream package

A stream package is not dependent on any datasets that are not included in the stream package.

self-healing of data

The detection and repair of data inconsistencies in a ZFS system by the system itself, due to the ZFS feature of data redundancy provided through mirrored and RAID-Z configurations. See also ZFS redundancy.

SendTargets discovery

A dynamic target-discovery method. See also dynamic discovery.


(share file system) A virtual file system that provides read-only access to the table of shared file systems for the local system.

simple LU mapping

See LU mapping.


(Server Message Block) A network-based file system protocol that enables Windows and Mac clients remotely access files or directories stored on a native Oracle Solaris server. The shared file systems are mounted on each of those Windows and Mac clients. A Solaris SMB server can operate in either workgroup mode or in domain mode. In workgroup mode, the Solaris SMB server is responsible for authenticating users locally when access is requested to shared resources. This authentication process is referred to as local login. In domain mode, the Solaris SMB server uses pass-through authentication, in which user authentication is delegated to a domain controller.

SMI disk label

A type of VTOC label traditionally used in Oracle Solaris for disks smaller than 2 terabytes. See also VTOC label.


A read-only copy of a file system or volume at a given point in time. Snapshots can be created almost instantly, and they initially consume no additional disk space within the pool. However, as the dataset from which the snapshot was created changes, the snapshot uses disk space for referencing the old version of this dataset, thus preventing the loss of the old data.

snapshot stream

A form of data created by using the zfs send command on a snapshot of a ZFS file system or volume. This converts the snapshot into a snapshot stream, which is then used to re-create a ZFS file system or volume by using the zfs receive command. A snapshot stream can be a full stream or an incremental stream. A full stream consists of all dataset content from the time that the dataset was created up to the specified snapshot, while an incremental stream consists of the differences between one snapshot and another snapshot.

snoop tool

snoop is a diagnostic tool that enables you see data being passed on the network.

Socket Direct Protocol

See SDP.


(special file system) Virtual file system that provides access to character special devices and block devices.


(SCSI RDMA Protocol) A protocol for sharing SCSI based storage over a network that provides RDMA services, such as an InfiniBand (IB) network. See also RDMA and IB.

SVR4 package format

A legacy package format. If you wish to install device drivers packaged in SVR4 (System V Release 4) format, use the pkgadd command instead of the pkg install command.

static discovery

A static target-discovery method. See also discovery method.


(SCSI Target Mode Framework) The framework used by COMSTAR to manage target storage devices. See also COMSTAR.

storage area network

See SAN.

StorageTek Manager

See I/O multipathing.

stream package

A stream type that contains one or more streams. The three types of stream packages are: replication stream package, recursive stream package, self-contained recursive stream package.

STREAMS module

A defined set of kernel-level routines and data structures that is dynamically pushed on the stream from the user level by an application. The STREAMS module performs the functions of a typical module, such as converting lowercase characters to uppercase, or adding network routing information.


(swap file system) A virtual file system used by the kernel for swapping, swapfs controls the allocation of anonymous memory pages, leading to the greater memory page management flexibility of Oracle Solaris virtual swap space. See also anonymous memory and virtual swap space.

symmetric storage devices

A storage device in which all paths to the storage device are active, and I/O commands can be issued through any path.

system dump

See dump device.

target group

A set of targets.

temporary file system



(target portal group) A list of IP addresses that determines which interfaces a specific iSCSI target will listen to.


(temporary file system) A virtual file system that uses local memory for file system reads and writes. Using TMPFS improves system performance by saving the cost of reading and writing temporary files to a local disk or across the network. Using TMPFS to hold these temporary files significantly speeds up create, manipulate, and delete operations. Files in TMPFS file systems are not permanent. These files are deleted when the file system is unmounted and when the system is shut down or rebooted. TMPFS is the default file system type for the /tmp directory in the Oracle Solaris OS. You can copy or move files into or out of the /tmp directory,as you would in a ZFS or UFS file system. The TMPFS file system uses swap space as a temporary backing store.

transactional semantics

A data management methodology that always keeps the ZFS file system state consistent on disk. Data is never overwritten, and copy-on semantics is used. Any sequence of operations is either entirely committed or entirely ignored, resulting in a file system that can never be corrupted through accidental loss of power or a system crash, as can happen with older data management methods that overwrite data in place.


(User Direct Access Programming Library) A standard API that enhances performance of data center applications for data messaging and provides scalability and reliability of RDMA - capable interconnections such as InfiniBand (IB). The uDAPL interface is defined by the DAT Collaborative organization. See also RDMA and IB.


(Universal Disk Format file system) The industry-standard format for storing information on the optical media technology called DVD (Digital Versatile Disc or Digital Video Disc).


(Unified Extensible Firmware Interface) A firmware interface between an operating system and the platform, designed to replace, while providing legacy support for the BIOS firmware interface. UEFI can support remote diagnostics and repair of computers, even with no operating system installed. UEFI also protects against bootkit attacks, ensures faster startup, and provides support for drives larger than 2.2 terabytes (TB) and for modern, 64-bit firmware device drivers.


(UNIX file system) A legacy disk-based file system used by UNIX operating systems such as Oracle Solaris.


Oracle Solaris USB Architecture.

Version1 format

See bit-masking format.


(virtual file system) A memory-based file system that provides access to special kernel information and facilities. Most virtual file systems do not use file system disk space.

virtual device

A logical device in a pool, which can be a physical device, a file, or a collection of devices.

Virtual devices

An internal representation of the disk devices or files that are used to create a storage pool. Virtual devices describe the layout of physical storage and the storage pool's fault characteristics.

virtual file system

See VFS .

virtual swap space

A layer between anonymous memory pages and the physical storage that backs these pages. A system's virtual swap space is comprised of its physical swap space and a portion of the currently available physical memory. Virtual swap space reduces the size of physical swap space and increases the flexibility of managing memory pages. See also anonymous memory and swapfs.


(virtual local area network) A subdivision of a local area network at the datalink layer of the protocol stack.


(virtual network interface card) A virtual network device that behaves just like a physical NIC when configured. A VNIC is configured over an underlying datalink to share it between multiple zones or virtual machines (VMs) or to connect the VNIC to an elastic virtual switch.


See ZFS volume.

Volume Table of Contents

See VTOC label.

VPPA device

(virtual physical point of attachment device) A device that binds a communication service to a combination of a port and a partition key.

VTOC label

(Volume Table of Contents label) You apply a VTOC label to a disk after you change its slices or partitions, to make the slices available to the OS. You can use a VTOC label on a disk of any size, but the space addressable by the VTOC label will be limited to 2 TB. Oracle Solaris supports the following VTOC labels:

  • SMI – Traditional label for disks sized less than 2 TB.

  • EFI – Label for disks sized larger than 2 TB.

  • EFI(GPT) – Label for disks less than 2 TB. For more information, see EFI (GPT).


Network monitoring and packet analyzer tool. It can be used for troubleshooting iSCSI protocol and configuration problems.

workgroup mode

A mode of operation of the Oracle Solaris SMB server.

World Wide Name

A unique identifier of SAN-connected devices such as HBA ports. The WWN is analogous to the unique MAC address of a network card.

wrapping key

A key used to encrypt the actual data encryption keys during the encryption of electronic data.


See World Wide Name.

xHCI host controller

(eXtensible Host Controller Interface) A USBA (Solaris USB Architecture) compliant nexus driver that supports the eXtensible Host Controller Interface Specification 1.0, an industry standard developed by Intel. Mass storage devices and the USB hub that support USB 3.0 can both work in the USB 3.0 mode when they are connected with eXtensible host controller interface (xHCI) ports. All the other legacy USB devices other than the USB audio and video devices continue to work when they are connected to xHCI ports.


The default disk-based and root file system for Oracle Solaris. ZFS manages physical storage by aggregating devices into a storage pool, instead of by creating virtualized volumes. The storage pool acts as an arbitrary data store from which file systems can be created. File systems are thus no longer constrained to individual devices, but can share disk space with all file systems in the pool. File system size need not be predetermined, as file systems automatically grow by using new storage added to the storage pool disk space.

ZFS volume

A dataset that represents a block device.

ZFS storage pool

See ZFS.

ZFS snapshot

See snapshot.

ZFS reservation

A ZFS reservation is an allocation of disk space from the pool that is dedicated to a dataset. You can reserve disk space for a dataset only if that space is currently available in the pool.

ZFS redundancy

See redundancy.

ZFS data scrubbing

See scrubbing.

ZFS data resilvering

See resilvering.

ZFS clone

See clone.


An execution environment consisting of software applications and services isolated from the rest of the Oracle Solaris operating system (OS) by using flexible software-defined boundaries. Multiple zones can be created within a single instance of the Oracle Solaris OS, each behaving as an independent OS separate from the underlying hardware. The Oracle Solaris OS supports three types of zones: global, non-global, and kernel.